Filtration Systems by cPitDSc


									Overall this was a good effort and a well done paper. However the grade was adversely affected by
numerous technical errors such as poorly done trade studies, poor research, and failing to consider options
for some systems (just choosing an existing one with no analysis). Specifics of the grading: 7
Administrative/format errors (-3 points), 9 Typographical or attention to detail errors: (-5 points),
Numerous Content / Technical errors: (-22 points). Your group did go into more depth in some areas (+5)
Final grade 75%
                                                                                                      Col Voss

       Mars Exploration Initiative: Environmental Control Life

                               Support Systems Analysis

                                          18 November 2004

                                 AERO 4730-Space Mission Design I

                                Space and Life Sciences Directorate

        Brandon Bethune      ____________________________________________________

        Hailey Hartwell      ____________________________________________________

        Ashley McDonald      ____________________________________________________

        Jason Park           ____________________________________________________

        Matt Read            ____________________________________________________

        Sarah Whalley        ____________________________________________________

        J.P. Wilson          ____________________________________________________

       It has been the intent of ORBITZ, Inc. to develop a design concept for the Environmental

Control and Life Support System (ECLSS) for the Crew Exploration Vehicle (CEV) that is

anticipated to launch in 2014. The duration of the mission is expected to be a total of nine months,

including contingency time. Areas that have been analyzed include oxygen production, water

purification, temperature and humidity control, food, sanitation, waste management, caution and

warning, fire detection and suppression, pressure monitoring and regulation, and gas analysis

systems. The weighted factors trade study methodology has been used to analyze each area in depth.

Based on the outcome of the trade study results, a system concept has been developed.

       The ECLSS design concept will incorporate the Atmospheric Composition Monitor (ACM)

to monitor the atmosphere onboard the CEV. The technology utilized by the Sabatier carbon dioxide

removal system will be used in conjunction with an electrolysis process to complete a totally

regenerative cycle for oxygen production and carbon dioxide removal. Carbon dioxide removal will

be filtered using 2-bed molecular sieves. Condensing Heat Exchangers (CHX) will be used in

conjunction with Flexible Metal Fabric radiators. Pre-packaged food will be brought onboard and a

plant habitat will be used to supplement the diets of the crew. The waste management system that is

currently used onboard the International Space Station will be used onboard the CEV. The

wastewater will be recycled and filtered and the solid waste will be used as fertilizer for the plant

habitat. A caution and warning system, fire detection and suppression, and pressure control system

will be incorporated into the CEV.

                                                           Table of Contents

Summary ........................................................................................................................ ii

Acronyms and Nomenclature ......................................................................................... iv

List of Figures ................................................................................................................. v

Introduction .................................................................................................................... 1

Part I Technical Concepts and Systems Considered ......................................................... 2

Part II Trade Studies and Results ..................................................................................... 7

Part III Technical Solution, Integration and Concept Definition .................................... 16

References .................................................................................................................... 30

Appendix 1.0: Air ........................................................................................................ 31

Appendix 1.1: Atmosphere Monitoring System ............................................................ 32

Appendix 1.2: Oxygen Production and Carbon Dioxide Removal................................. 34

Appendix 1.3: Trace Contaminant Control System ....................................................... 36

Appendix 2.0: Food ...................................................................................................... 38

Appendix 2.1: Food Type Trade Study ......................................................................... 39

Appendix 2.2: Plant Type Trade Study ......................................................................... 41

Appendix 2.3: Menus ................................................................................................... 43

Appendix 4.0: Waste Management System................................................................... 46

Appendix 6.0: Water Recovery and Supply .................................................................. 48

Appendix 10.0: ECLSS Documents.............................................................................. 50

Appendix 10.1: ECLSS Mass and Volume Budgets...................................................... 51

Appendix 10.2: ECLSS Diagram .................................................................................. 53

Appendix 10.3: Habitat Schematic .............................................................................. 55

             Acronyms and Nomenclature

ACM      =     Atmospheric Composition Monitor
ASC      =     Airlock Support Components
AWRS     =     Advanced Water Recovery System
CAMS     =     Central Atmosphere Monitoring System
CDH      =     Command and Data Handling
CDRA     =     Carbon Dioxide Removal Assembly
CEV      =     Crew Exploration Vehicle
CHX      =     Condensing Heat Exchangers
CO2      =     Carbon Dioxide
CWP      =     Condensate Water Processor
ECLSS    =     Environmental Control and Life Support System
FAE      =     Fixed Alkaline Electrolytes
FMF      =     Flexible Metal Fabric
GA       =     Gas Analyzer
GCMS     =     Gas Chromatograph/Mass Spectometer
ISS      =     International Space Station
LiHO     =     Lithium Hydroxide
LiOH     =     Lithium Hydroxide
LMLSTP   =     Lunar Mars Support Test Project
MCA      =     Major Constituent Analyzer
MDM      =     Multiplexer/Demultiplexers
MS       =     Mass Spectrometer
NDIS     =     Dispersive Infrared Spectrometer
O2       =     Oxygen
PCS      =     Pressure Control System
TCCS     =     Trace Contaminant Control System
TGM      =     Trace-Gas Monitor
THC      =     Temperature and Humidity Control
TRL      =     Test Readiness Level
WMS      =     Waste Management System
                                                 List of Figures and Tables

Figure 1: FAE Schematic ............................................................................................. 19

Figure 2: Condensing Heat Exchanger and Slurper ....................................................... 23

Figure 3: CHX Flow Diagram ...................................................................................... 24

Figure 4: AWRS Schematic ......................................................................................... 26

Figure 5: Caution and Warning Classifications ............................................................. 27

Figure 6: Water Mist System Schematic ........................................................................ 28

Table 1: Waste Products ............................................................................................... 25

       It is the intent of a design team representing ORBITZ, Inc. to design the Environmental

Control and Life Support System for the Crew Exploration Vehicle. The Crew Exploration Vehicle

will be launched to Mars in 2014. The duration of transit time will be approximately nine months.

The Environmental Control and Life Support System must be able to sustain life of three astronauts

for the entirety of the transit time, approximately 270 days one-way. Upon arrival to the Martian

surface, new supplies will be provided.

       The areas the design team will evaluate are oxygen production, carbon dioxide removal,

water supply, temperature control, humidity control, food, sanitation, fire detection, caution and

warning, pressure control, and waste management. The goal of ORBITZ, Inc. is to design necessary

aspects of survival for the spacecraft. The spacecraft should be as small and lightweight as possible

while marinating effective and efficient performance. One of the major decisions of ORBITZ, Inc.        Comment [v1]: I don’t think marinating is the
                                                                                                        correct word – perhaps maintaining?

is to determine the choice of cabin pressure. Almost every decision regarding the spacecraft depends

on this pressure. This pressure will dictate the design for all Environmental Control and Life

Support Systems under consideration.

Part I Technical Concepts and Systems Considered

          Various technologies are being considered in the areas of atmosphere monitoring, oxygen

production, carbon dioxide removal, food, temperature control, humidity control, waste

management, sanitation, and water supply.

1.0 Air

1.1 Atmosphere Monitoring System: Ashley McDonald

          The Russian Gas Analyzer (GA), American Atmospheric Composition Monitor (ACM),

Central Atmosphere Monitoring System (CAMS), and a prototype Trace-Gas Monitor (TGM) are

technologies being considered to monitor the atmosphere and living environment onboard the CEV.

The atmospheric monitoring system should monitor gaseous element levels that make up a desired

atmosphere. These elements include: nitrogen (N), oxygen (O2), carbon dioxide (CO2), carbon           Comment [v2]: Be consistent with nomenclature
                                                                                                      – either subscript or don’t with chemical formulas.
                                                                                                      CO2 or CO2
monoxide (CO), and hydrogen (H).

          The Gas Analyzer is comprised of two analyzer subsystems. One analyzer monitors O2,

CO2, and water (H2O) by taking partial pressure measurements. A separate CO gas analyzer

provides analog signals and discrete signals to computer sensors.

          The Atmospheric Composition Monitor is composed of three major components, which

performs tasks ranging from measuring the amount of elements in the air, to measuring trace organic

contaminants. This system is continually collecting data and processing information to maintain an

adequate living environment for the crew on board the International Space Station (ISS) [Niu].

          The Central Atmosphere Monitor System (CAMS), developed by the Naval Research

Laboratory, is a combination carbon dioxide detector and fixed-collector mass spectrometer that       Comment [v3]: I like that you ofund other
                                                                                                      possible solutions

monitors hydrogen, water, nitrogen, carbon monoxide, oxygen, carbon dioxide, and refrigerant

gases. The system became the first submarine air monitor to be "service approved" and was

subsequently installed on all U.S. Navy nuclear submarines. NASA also uses a variant of this system

for manned space vehicles.

          The Trace-Gas Monitor is a line up of units that provide ultrahigh sensitive, highly

accurate, continuous monitoring of trace amounts of impurities contained in gases (N2, O2, He, Ar,

H2, and Air) used in the semiconductor manufacturing process The units are equipped with a

maximum two-component function within the one-component analysis capability for CO, CO2, and

CH4 . Also, a self-monitoring function for the flow volume (pressure), chopper motor

(electromagnetic valve), fire warning and electrical source warning systems provides users with

quick alerts to any irregularities.

1.2 Oxygen Production and Carbon Dioxide Removal: Matt Read

        Oxygen production onboard the CEV is one of the most vital systems involved, as is the

removal of carbon dioxide from the atmosphere. The combination of these two functions to create a

single regenerative cycle is a new technology being considered for use on the CEV. Since mass and

volume are two of the most important considerations in sending a vehicle to Mars, the combination

of oxygen production and carbon dioxide removal is imperative. The ability to use plants to remove

CO2 and produce O2 is by far the best technology, since the system is completely regenerative and

food is produced as a byproduct. However, there are too many complications with the use of plants

to create a self-sustaining system in order for it to be ready by 2014. The combination of the

Sabatier and electrolysis processes will be considered as the main O2 production and CO2 removal

systems. Other systems being considered for CO2 removal are the Vozdukh, Carbon Dioxide

Removal Assembly (CDRA), and lithium hydroxide (LiOH) canisters. The Vozdukh is the Russian

system currently used onboard the ISS. The CDRA is an American system used as backup onboard

the ISS. Both of these systems are regenerative. LiOH canisters are the oxygen supply used on

space shuttle missions. These canisters are expendable and must be resupplied.

       For oxygen production, electrolysis is the only technology in development besides utilizing

plants. Pressurized oxygen tanks alone are too massive to use as the main supply system, but they

can be considered as an alternative method. A mini-ecosystem is currently under development for

supplying O2, however the likelihood of its perfection by 2014 is minimal.

1.3 Trace Contaminant Control System

               Another vital component of the Air Revitalization System is the Trace Contaminant

Control System (TCCS). With a total of 216 trace contaminants it is vitally important, especially for

long missions, to remove harmful chemicals that the carbon dioxide system overlooks. The TCCS

further improves chamber air quality by removing trace contaminants by means of activated

charcoal, spent LiOH, and a high temperature catalytic reaction

2.0 Food: Sarah Whalley

       Food is a vital entity that is needed for any mission crew to survive. The food consumed by a

crew must compensate for the energy that will be expended during daily activities as well as provide

all the essential nutrients that the body requires [Larson, 581]. This allows the crew to stay alive and

healthy while onboard a mission. It is important to minimize mass, volume, and food preparation,

however, only so much can be saved. For long duration missions, the variety of food is extremely

important. The crew members will be rotating a limited number of meals and monotony will result

in boredom and decrease the morale of the crew.

       It is estimated that the crewmembers will require 1.83 kg (4 lbs) of food per day [Larson,

585]. For a crew size of three, this estimation amounts to 1,482.3 kg (3,240 lbs) for a period of 270

days, which is the amount of time anticipated for this mission to Mars. There are two main

processes for providing food; carrying onboard food or growing food using a hydroponics system.

Carrying food onboard is currently the means of providing food for both the shuttle and the ISS. A

hydroponics system is currently undergoing testing onboard the ISS as a regenerative means of

providing food for future flight missions. The technologies being considered for food supply on the

CEV are carrying onboard the required food for the duration of the mission, growing a variety of

plants through hydroponics, and a combination of carrying onboard food and supplementing the diet

with small plant produce to add more variety.

3.0 Temperature and Humidity Control: J.P. Wilson

       The temperature and humidity control (THC) system regulates and monitors the temperature

and humidity levels of a habitat. The THC is needed in order to keep the crew comfortable and to

maintain a good working environment. Keeping the humidity at a safe level is important because it

prevents the electronic instrumentation from collecting condensation. The temperature should be

kept between a range of 17 – 35 oC and the humidity should be controlled with a dew point between

4 – 18 oC. To control the temperature and humidity, condensing heat exchangers (CHX), fans, and

filters will be considered. The CHX function is to accumulate heat loads from latent and sensible

sources that are expelled from the crew and equipment, respectively. To transfer the heat loads to

the CHX, fans with filters will be used to direct the cabin air toward the CHX. In order to expel the

heat that has been collected, radiators will be used. The two types of radiators that will be

considered are the current radiators that are onboard the ISS and a new technology that is

underdevelopment, Flexible Metal Fabric (FMF) radiators.

4.0 Waste Management System: Jason Park

       A waste management system (WMS) is essential to the CEV. Two currently developed

systems are being considered for possible use: the system being used onboard the space shuttle and

the system being used onboard the ISS. Both of these systems are integrated multifunctional

systems primarily utilized to collect and process bio-wastes from all crewmembers in a low gravity


5.0 Sanitation-Managing Housekeeping and Trash: Jason Park

       Cleaning and sanitation is an important consideration that can directly affect the crew. It is

imperative that the crew cleans the cabin to rid it of particulates and prevent fungal colonies from


6.0 Water Recovery and Supply: Hailey Hartwell

       The life support system onboard the proposed CEV must maintain and supply the crew with

all aspects needed for human life. The greatest single mass consumable is water. Each human

onboard the CEV requires approximately 5.5 kilograms of water per day for daily usage. The crew

members will use an additional 25.4 kg per person per day for tasks such as showering, clothes

washing, and dish washing. These tasks will occur approximately once a week.

       Without a regenerative water supply, the design would need to accommodate the storage of

approximately 14,400 kg of water. This is an unreasonable method of water supply because this

mass is more than the weight limit provided to the ECLSS on the CEV. Therefore, a water recovery

system must be designed. The two candidate technologies for consideration are the Condensate

Water Processor (CWP) and the Advanced Water Recovery System (AWRS). The CWP is currently

used to recover water condensate on the ISS. The AWRS system is a system in development at

Johnson/ Marshall Space flight center through the Advanced Life Support department.

7.0 Caution and Warning and Fire Detection: Brandon Bethune                                             Comment [v4]: Bad formatting – put titles of
                                                                                                        sections on the same page with the text

7.1 Caution and Warning

       The caution and warning system takes into consideration fire detection and suppression,

cabin depressurization, and monitoring of any off nominal conditions of crew safety. Information

from these monitoring systems travels through Multiplexers/Demultiplexers (MDMs) which are then

fed into a multiplexing system. This multiplexing system breaks down the combined information

sending it to the appropriate panel to alert the crew. The caution and warning alerts are interfaced

with the following systems: auxiliary power units, data processing system, environmental control

and life supports systems, flight control system, electrical power, guidance navigation and control,

hydraulics, and the main propulsion. The crew is alerted by visual cues and aural tones. The only

caution and warning system considered is the caution and warning system used on the Shuttle and

ISS. This system is simple and effective therefore no other systems need to be researched.               Comment [v5]: This is a bit narrow – there are
                                                                                                         many different ways to do C&W – you should have
                                                                                                         explored other options. Also the Shuttle and ISS
7.2 Fire Detection                                                                                       have different systems – you have not even
                                                                                                         compared them to choose the best of the two for this
       The fire detection and suppression is a subsystem of caution and warning. The system

detects ionized smoke particles in the air using sensors. Fires can be extinguished by means of

Halon 1301, CO2, or water mist.

8.0 Pressure Control: Ashley McDonald

       The Pressure Control System (PCS) consists of pumps and valves that mix the nitrogen and

oxygen in the specified percentages. The system also monitors the atmospheric pressure and

depressurizes the station when necessary to prevent over-pressurization or to extinguish a fire during

an emergency. The space shuttle orbiter utilizes a PCS that was developed by Carleton. This system

will be considered for possible integration to fit the needs of the CEV.

Part II Trade Studies and Results

       In order to choose the best individual systems for ECLSS, a trade study is preformed. First,

there is an assessment of the mission and the major factors that will contribute to deducing the best

system. To begin, a specifications sheet is created, as seen in. This sheet lists the specific criteria    Comment [v6]: As seen in ???

being analyzed for each system. This criterion often includes cost, mass, volume, and power

required. It can also include factors such as reliability, regenerative capabilities, and percent error.

These will be the factors that will help to determine the best overall mission to Mars. The

information calculated includes the mathematical findings based upon a 270 day mission with three


          Once the specification sheet is finalized, the factors are then normalized. This means that

each value on the specification sheet is given a numeric value between one and ten (ten being the

best). Each of these normalized values is then weighted based on weighting factors given to each

criterion. The weighted factors range from one to five (five being most important). Finally, the

normalized values are multiplied by the weighted factors for each criterion. Then the summation of

all criteria for each system is calculated to determine the best overall results. All trade study data

can be seen in the Appendices.

1.0 Air

1.1 Atmosphere Monitoring System: Ashley McDonald

          The Russian Gas Analyzer, American Atmospheric Composition Monitor, Central

Atmosphere Monitoring System, and a Prototype Trace-Gas Monitor are all researched and a trade

study is preformed to determine to the best possible system for this long duration mission. By use of

the weighted factors method, a sufficient Atmosphere Monitoring System is chosen. The trade study

concludes that the American Atmosphere Composition Monitor will be the best Monitoring system.

          The variables used in the trade study include: cost, total power required, total volume, total

mass, multi-functional, reliability, and present percent error. These variables have weighted values

which are utilized to determine the numerical output of the trade study. The minimal variables of

concern for this project are the cost, total power required, and present persent error.

       Due to the length of the mission to Mars, a very reliable system is necessary for this mission

to ensure a safe mission. Also, a minimal amount of space will be utilized. Therefore, the volume

and mass of the system are of much importance when deciding the appropriate system for this

specific mission. Since optimization of space is essential in this long mission the function of each

system must be considered. The systems that are capable of more functions (multi-functional) are

more desirable for this mission.

       After completion of a trade study between the Gas Analyzer, Atmospheric Composition

Monitor, Central Atmosphere Monitoring System, and a prototype Trace-Gas Monitor, it has been

determined that the most efficient system is the ACM. The American monitoring system has the

better performance over a length of time compared to the other systems considered.

1.2 Oxygen Production and Carbon Dioxide Removal: Matt Read

       A trade study has been completed for the CO2 removal system, comparing the four different

options available. Although a natural ecosystem is the best choice for long duration missions

because of its complete regenerative capability, it is not close enough to being finished for use on

this mission. The available technologies that are analyzed are the LiOH canister, the Vozdukh, the

CDRA and the Sabatier process. The traits that are deemed most important to this mission are mass,

volume, power required, TRL and safety. These traits are weighted according to their importance

then each system multiplied by the weighting factor to get the total score for that trait. Since mass

directly influences the cost of the launch and mission, it is deemed most important with a weighted

factor of five. The volume of the system is a close second with a weighted factor of four because it

relates directly to the mass of the overall system. The power required and reliability are not as

important and therefore have a weighted factor of two. TRL and safety both have a weighted factor

of one because safety is inherently covered by the dual-fault tolerant requirement, and all systems

considered are currently developed and tested.

       The LiOH canisters are a good choice for short missions because they are extremely reliable.

For long missions, however, the mass of the required canisters is too much. Inspecting the trade

study in Appendix 1.2, the Vozdukh and CDRA, appear to have similar results. However, they both

require a great amount of power. The best technology solution from analyzing the trade study turned

out to be the Sabatier process. It has a low volume and mass and extremely low power consumption.

These factors, along with the ability to merge the output with the oxygen production loop, make the

Sabatier a clear choice for the mission to Mars.

2.0 Food: Sarah Whalley

       The technologies being analysed are carrying all food onboard, growing all food, and a

combination of carrying food and supplementing the diet with harvested food. There are currently

eight categories of space food readily available that are used onboard the space shuttle and the ISS;

rehydratable, thermostabilized, intermediate moisture, natural form, irradiated, frozen, fresh, and

refrigerated foods. Some of these types of pre-packaged food will not be feasible due to the length

of the mission. For example, the amount of fresh and natural form foods will be limited due to the

long duration of the planned mission to Mars. In addition, it is important to minimize mass and

dehydrated foods result in the least mass due to the larger absence of water. For this reason, pre-

packaged foods being considered to provide all necessary nutrients will be mostly rehydratable,

thermostabilized, irradiated, and frozen foods. As a general rule, the higher water content that is in

food, the better it tastes. This added variety will play an important psychological role for the

crewmembers since they will be separated from the Earth for so long.

       Hydroponics is a method of harvesting plants in water rather than in soil. These plants

generally takes up less space than conventional methods and the plants are often larger and healthier.

Life sustaining nutrients are supplied to the plants through a liquid solution. Hydroponics would

require power sources for temperature control as well as lighting. A hydroponics system can make

use of carbon dioxide and human waste. A drawback of relying on hydroponics is the chance of the

crops dying, resulting in no available food for the crew.

       Careful consideration of what crops to cultivate must also be decided in order to provide a

well-balanced diet. The mass and volume requirements that are essential for each crewmember

when utilizing a hydroponics system is also rather large. It is estimated that each crewmember will

require 15-20 m3 of plants per day for food [Larson, 561]. Including contingency time, this amounts

to 27 m3 of plants per crewmember per day. This would result in exuberant mass and volume                Comment [v7]: If it is per crewmember day, why
                                                                                                         is it more m3 for a longer stay?
                                                                                                         Comment [v8]: Word choice? Maybe excessive?
amounts. To compensate for this, a combination of carrying onboard food and growing small plants

appears to be a more reasonable solution.

       A weighted factors trade study analysis will yield the most efficient and economical means of

providing food for a mission crew of three for a duration time of nine months. To complete the food

technology analysis, the parameters that are considered are mass, volume, power required, TRL,

launch cost, reliability, and variety. Mass and reliability are most important. The less mass required

results in the less the system will cost to launch. Reliability is most important because food must be

available for survival of the crew members. TRL is important because the technology should be

available and tested by 2014. Additional determination data can be viewed in Appendix 2.0 for the

food technologies considered.

       Completing a weighted factors method trade study reveals that the best food technology for

the proposed mission is to carry onboard food and grow small crops to supplement the diet. This

will enhance the variety of food available as well as psychologically aiding the crew members by

having them grow the crops, giving them tasks to perform. Carrying onboard food is a technology

that can be considered equally advanced and available if substitutions must be made. Hydroponics,

however, does not appear to be a technology that will be worthwhile. The results from the trade

study can be seen in Appendix 2.0.

       Maintaining a miniature greenhouse will provide the crew with a task at hand as well as

providing variety in the food for the 9 month duration for the trip to Mars. Algae are easy to grow

and are rich in vitamins and protein. It is suggested that algae should not exceed 20% of a diet

(Eckart, 273). In addition, they convert carbon dioxide into oxygen, which will aid in providing

supplemental oxygen to the crew [Larson, 559]. Drawbacks to having algae in a diet are the

crewmembers are prone to belching, nausea, and loss of appetite; however these symptoms pass after

a few days [Eckart, 273]. Other possible plants to harvest include broccoli, carrots, lettuce, and

sunflowers, tomatoes, alfalfa, and beans. A trade study has been completed to evaluate which plants

would be most beneficial to grow. The trade study for this analysis can be viewed in its entirety in

Appendix 2.1.                                                                                          Comment [v9]: You did not say anything about
                                                                                                       the equipment or hardware to prepare the food – this
                                                                                                       is a significant design consideration – convective
3.0 Temperature and Humidity: J.P. Wilson                                                              oven or microwave?, freezer or not? How do you
                                                                                                       add water to the dehydrated food? Where are you
                                                                                                       stowing all the food?
       A decision concerning the type of radiator to be used onboard the CEV must be made. The

candidate solutions are FMF and the current ISS radiators. The FMF radiators occupy less than half

of the area that the ISS radiators require. The FMF radiators have a mass per area of less than 3.7

kg/m2, whereas the current ISS radiators are 8.5 kg/m2. This reduction in mass and volume indicates

that the FMF radiators are the better candidate solution.

4.0 Waste Management System: Jason Park                                                                Comment [v10]: Bad format – section title
                                                                                                       should be with text

       The WMS has two possible system choices: the current shuttle system, and the ISS system.

The system used on the space shuttle allows solid waste to be collected, compacted, and stored into

expendable canisters. The shuttle system is comprised of a commode, urinal, fan separator, odor and      Comment [v11]: This true only for the extended
                                                                                                         duration WCS

bacteria filter, vacuum vent quick disconnect, and a WMS control. The commode contains a single

multi-layer hydrophobic porous bag liner that is used for collecting and storing solid waste. The

urinal assembly is comprised of a flexible hose with attachable funnels. These attachable funnels

can accommodate both men and women and can be used while sitting, standing, or floating at any

altitudeattitude. This assembly provides the capability to collect and transport liquid waste to the

specified wastewater tank. Fan separators are used to transport air flow through the commode and

urinal. This allows the waste liquid to be separated from the air flow and be transported to the

wastewater tank. The air is then filtered through the odor and bacteria filter to remove odors and

bacteria from the air. The air is then returned to the crew cabin. Excess waste liquid can be vented

to outer space through the vacuum vent quick disconnect. The WMS control is a series of switches

that are used to configure the commode for the different operational modes.

       The ISS utilizes a similar waste management assembly. The ISS system being considered is

composed of a solid waste container, porous inserts, solid waste receptacle, a fan, toilet receptacle,

pre-treat and water dispenser, and an air-water separator. Solid waste is collected in porous inserts,

which are held in place by the solid waste container. The porous inserts are then stored in the solid

waste receptacle. A fan is used to move waste into the solid waste receptacle by using suction. The

toilet receptacle consists of a funnel. The waste liquid and pre-treat water enter separate chambers

through the air-water separator. This device drains the liquid and transports it to a urine container.

       These two systems are evaluated using a weighted factor trade study, which can be viewed in

Appendix 4.0. The trade study considers the variables of: system mass, supplies mass, system

volume, supplies volume, TRL, and connection accommodation. The mass and volumes of both

system and supplies needed were considered to be the highest weighted factors because they are the

most limited resources. The ISS system is determined to be the best system to meet the needs of the


5.0 Sanitation-Managing Housekeeping and Trash: Jason Park

       Sanitation wipes will be used to clean the cabin and crew compartments of particulates. A

trash compactor will be used to minimize the volume of waste that will be produced.

6.0 Water Recovery and Supply: Hailey Hartwell

       A trade study was completed to compare the candidate solutions for a water recovery system.

The candidate solutions are the CWP and the AWRS systems. The CWP recovers condensate from

the air and purifies it into usable water for the drinking and food preparation for the crew.

Condensate forms in the air on board a spacecraft from skin evaporation and water released during

crew respiration. The AWRS system is a total regenerative system. The system recovers all water

on board including waste water. This system has been developed, built, and tested at the Johnson

Space Center. The Lunar Mars Life Support Test Project (LMLSTP) tested the complete AWRS

system in Phase III of testing in 1997. The 90 day test successfully utilized the system to recover

waste water and reproduce it as potable water. The AWRS system is capable of recovering

approximately 108.4 kg of water daily. The three person crew on the CEV will use at maximum

92.7 kg per day. This system will easily be ready for space flight for the launch in 2014. After the

successful Earth testing, the only step left in the Technology Readiness Level (TRL) scale is to fly

the system on a spacecraft. These two candidate systems are compared and considered using the

trade study analysis method.

       The trade variables that are examined include: the mass of water to be brought, mass of the

system, volume of water stored, volume of the system, power required, TRL, recovery efficiency,

cost of system, and cost to launch. For this spacecraft, the most important variables are mass and

volume because they are the most limited resources. Therefore, these are weighted the highest with

a value of four. For the water recovery system on the CEV, the trade study has determined the

AWRS to be the best solution. The AWRS far out preforms performs the CWP system in the trade

study. The AWRS is the best solution because it requires far less mass and volume than the CWP.

7.0 Caution and Warning and Fire Detection: Brandon Bethune

7.1 Caution and Warning

       A caution and warning system using aural and visual cues for the crew will be the system of

choice for detecting off nominal conditions. This system is modeled after the system used onboard

the ISS.

7.2 Fire Detection and Suppression

       Halon and ionization sensors will be used for fire suppression and detection. These have          Comment [v12]: Halon is not a detector

been chosen for this mission because of the success on the ISS and U.S. shuttles. They have proven

to be very accurate and precise. This type of fire suppression weighs very little and can be contained

in small areas. It also has a very high reaction time which causes the suppression of fire to result

quickly. The Halon 1301 gas can be very harmful for humans, however.

           CO2 tanks and water mist, on the other hand, require more weight and volume yet are low

toxicity, low cost and proven to be effective. Halon 1301 will be used on the CEV for pressurized

equipment bays external to the crew cabin after taking into consideration the pros and cons for each

one. The water mist system shall be used in the crew cabin after considering the low toxicity and

high efficiency in microgravity. Water mist is a viable alternative to water-based systems because

the system is much lighter.

8.0 Pressure Control: Hailey Hartwell and Sarah Whalley

          The PCS that will be used onboard the CEV to mix the nitrogen and oxygen into the

specified percentages is the same system used on the space shuttle orbiter. The PCS provides a two-

gas atmosphere of nitrogen and oxygen to the crew compartment and habitable payload modules. It

also supplies oxygen to the emergency breathing masks and the ASC subsystem. Nitrogen for

pressurization of the potable and waste water tanks is also supplied by the PCS.   The PCS will also

monitors the pressure levels to keep them in the nominal range of 70.0 -71.0 psia. The pressure is      Comment [v13]: This is a disconnect with the
                                                                                                        Structures Team – they said in their report that the
                                                                                                        internal pressure was to be higher than this.
lower than atmospheric pressure to allow for minimal structural mass. This is also the pressure at an

altitude of 10,000 ft, so ecosystems are capable of functioning properly while maintaining human

physiology at a functional level.

Part III Technical Solution, Integration and Concept Definition

          The technical ECLSS design developed will implement a regenerative CO2 removal and O2

production system. The Sabatier system will remove CO2. The methane byproduct will be vented

to space and the water byproduct will be routed to the oxygen generating system, which will use

electrolysis. The hydrogen byproduct will be routed back to the Sabatier process to close the loop.

The Atmospheric Composition Monitor will maintain the atmosphere by monitoring the levels of

nitrogen, carbon dioxide, and hydrogen.

1.0 Air

1.1 Atmosphere Monitoring System: Ashley McDonald

          The ACM will monitor the elements which are most vital to the atmosphere onboard the

CEV. The MS is an instrument which can measure the masses and relative concentrations of atoms

and molecules of each element [Van Bramer]. The three major components of the ACM are the

Major Constituent Analyzer (MCA), Gas Chromatograph/Mass Spectrometer (GCMS), and the Non-

Dispersive Infrared Spectrometer (NDIS).

       The MCA monitors the elements which are most vital to the atmosphere within the CEV.

These elements include: nitrogen, oxygen, carbon dioxide and hydrogen. The MCA uses a

monitoring system known as the Mass Spectrometer (MS). The MS is an instrument which can

measure the masses and relative concentrations of atoms and molecules of each element. As air

enters the inlet, the MS produces charged particles (ions) from the elements that are to be analyzed

and then uses electric and magnetic fields to measure the mass of the charged particles. A magnetic

field within the Magnetic Analyzer separates ions according to their momentum and then a detector

produces a signal from the separated ions. This signal is sent to an interpretive computer which

processes the data for results, which can then be analyzed by the ground control or other computers

(Van Bramer).

       In addition to measuring the major constituents in the atmosphere, the MS can also aid the

monitoring of trace contaminants. The CEV will utilize a Gas Chromatography/Mass Spectrometry

to monitor and measure the trace contaminants on board. Trace contaminants can be very hazardous

in space because the decreased buffering capacity to dilute contaminants. Some examples of trace

contaminants are off-gassing, crew byproducts, and scientific experiments.

       The combination of the Gas Chromatography and MS has the ability to separate complex

mixtures and obtain structural information about the individual trace contaminants. Gas

Chromatographic effluent is in the vapor state and can be admitted directly into the MS. After

traveling through the Gas Chromatographic capillary columns and high capacity vacuum pumps for

Mass Spectrometers the Gas Chromatographic effluent is fed directly into the ion source. Aside from

the capillary Gas Chromatographic system, the major components of the trace contaminant monitor

itself are: an ionization source, a mass separator, and an ion detector. With all these technical

components combined, the trace contaminant monitor ultimately filters the cabin air to remove trace

odors and volatile chemicals from leaks, spills and out-gassing.

        The third major component of the Atmospheric Composition Monitor is the Non-Dispersive

Infrared spectrometer. The major purpose of this spectrometer is to monitor the carbon monoxide

levels on board the CEV. The carbon monoxide analyzer uses a non-dispersive infrared detector

coupled with gas filters to rid the atmosphere of any harmful agents. The infrared source and

chopper filters rid the sample of air of other elements and compounds. Then, after passing through

the 3-Way solenoid valve the carbon monoxide then flows through a catalytic carbon monoxide

scrubber. Finally, after being cleaned of impurities, it is then pumped into a tube which sends

information to an infrared detector and proceeds out the outlet tube (Niu).

1.2 Oxygen Production and Carbon Dioxide Removal: Matt Read

        A merged technology for the CO2 removal process and oxygen production will be

implemented into the CEV concept design. The Sabatier reaction will be used to remove CO2 and

electrolysis will be used for oxygen production.

        The Sabatier process consists of an exothermic reaction that occurs spontaneously at

temperatures above 150°C in the presence of a catalyst. The chemical reaction for the Sabatier

reaction is:

This reaction only works in the presence of large amounts of CO2. 2-bed molecular sieves are used

to capture the CO2 from the cabin air. After being exposed to a vacuum, the CO2 is released and sent

to the reactor. The hydrogen is supplied for the reaction via an onboard supply tank. The hydrogen

is then combined with the carbon dioxide in the presence of an aluminum supported ruthenium

catalyst to produce methane gas and water. This process controls the CO2 levels, keeping them

below an average level of 1013 Pa. Since the water is in vapor form, it is condensed and collected in

a separator. Methane gas and water are byproducts produced. There are two options for the

methane that is produced: it can either be vented overboard via a non-propulsive device, or it can be

stored and used as a propellant for the various control systems. The water is captured and sent to the

oxygen production system for operation.

       Once the water is sent to the oxygen production system, it is combined with a catalyst and

sent to the electrolysis process. After undergoing electrolysis, the water is split into O 2 and H2

molecules. A new technique that employs Fixed Alkaline Electrolytes (FAE) will be used for this

                                                            process and can be seen in Figure 1. In

                                                            this new technology, the electrolyte is

                                                            fixed in a porous matrix. Water is pumped

                                                            through the water compartment for

                                                            simultaneous use as feed and coolant. The

                                                            hydrophobic porous membrane only

                                                            admits water in the vapor phase and

                                                            prevents direct contact between the coolant

                                                            and the electrolyte. The difference in

                                                            partial pressure drives this reaction. Both

                                                            electrodes are porous, allowing for the

                                                            exchange of water vapor and the product

             Figure 1: FAE Schematic

gases (hydrogen and oxygen). An electrolyte is sandwiched between the         electrodes and is held

inside the matrix and electrode system by capillary forces. This new FAE technology is beneficial in

many ways. The system is very compact and lightweight, with a high electrical efficiency. The

gases produced are dry enough, eliminating the need for a phase separator. Perhaps the most

important aspect of the new FAE is the increased safety. Since the electrolyte is in a matrix, the old

corrosive liquid electrolyte is no longer needed. In turn, the electrolyte pump is eliminated allowing

for safer overall operation in micro-gravity conditions. The oxygen production process maintains

the cabin O2 level at 2.95-3.45 psia. The pressurized oxygen tanks, which are used if the                 Comment [v14]: This results in 40% O2 nwhich
                                                                                                          is too high

electrolyzer fails or if rapid depressurization occurs, supply pure oxygen either directly to the cabin

or to emergency breathing masks. The cabin pressure in case of an emergency will be maintained at

less than 26% at 14.7 psia to 40% at 8 psia.                                                              Comment [v15]: That is the specification for a
                                                                                                          14.7 psi cabin, but you are using a different pressure
                                                                                                          – so what are your numbers?
         The hydrogen that is produced as a byproduct of the electrolysis reaction will be routed

back to the Sabatier reactor and fed back into the CO2 reaction. This step closes the regeneration

cycle. The main disadvantage of this process is that twice as much hydrogen is consumed as can be

recovered by the electrolysis process. In order to balance out the reaction, hydrogen must be

resupplied. This will be accomplished by routing hydrogen from the storage tanks used by the

structures group. The excess methane gas will be vented to space.

1.3 Trace Contaminant Control System

       On a mass basis, water vapor and carbon dioxide are the most significant atmospheric

contaminants onboard manned spacecraft. However, a variety of trace organics may be present.

These must be removed to ensure the health of the crew. Onboard the CEV, this function is

performed using thermally regenerable activated carbon beds. Activated carbon is an excellent

sorbent for removal of a broad variety of airborne organic contaminants. It is readily regenerated

thermally using a small flow of non-oxidizing purge gas or under vacuum conditions.

       The TCCS utilizes a Catalytic Oxidizer Assembly (COA) which oxidizes organic

compounds, producing CO2 and H20. Also, it burns inorganic compounds producing acidic gasses.

A sorbent Bed Assembly is used to remove these acidic byproducts of the COA such as hydrogen

chloride and sulfur dioxide. After going through the sorbent beds the air passes to the fan assembly

which moves air to the charcoal bed assembly. A flow meter assembly then regulates the amount of

air that goes to the COA.

2.0 Food: Sarah Whalley

       Carry on food will be the main source of food and 10% of the diet will be supplemented with

small plants. The plants that will be grown onboard the CEV are carrots and broccoli. Lettuce and

sunflowers were extremely close to alfalfa and beans, which allow the design team the freedom of

choice for the third plant. Lettuce has been chosen because it best complements carrots and broccoli

and can be combined to create a more complete meal. In addition, lettuce is the most popular of

these choices.

       Redehydrated, frozen, and irradiated carry on food will be used. The frozen food will be

stored in a freezer and the shelf-stable foods will be stored in racks. The small plants will be housed

in an enclosed hydroponics system. Carbon dioxide will be filtered into the greenhouse to

supplement plant grow. Elements and compounds from human waste will be processed through a

filtering system and provide necessary nutrients to the plant habitats. Water will be circulated          Comment [v16]: Is human waste a suitable

through the greenhouse to maintain proper water levels for plant growth. Using hydroponics will

allow regenerative systems to be largely used.

       Having a greenhouse onboard the space ship would psychologically aid the crewmembers,

giving them something to nurture and occupy their time with while they are in transit. It will also

add necessary variety to food consumption.

       Crew members will repeat meals every 21st day. This results in a 20 day meal cycle. This

cycle can be seen in Appendix 2.3.

3.0 Temperature and Humidity: J.P. Wilson

       The Condensing Heat Exchangers (CHX) are used to control the temperature and humidity.

The CHX being used are plate fin heat exchangers. They are being used because they result in

minimum mass and volume. At maximum effectiveness and reasonable pressure drops, they have

proven to be superior [Eckart, 211]. Two CHX units will be needed to control the habitat. Each of

them will be able to remove 20 kW of heat from the cabin air. They work by transferring internal

heat loads and external heat fluxes to a water coolant loop. Heat is generated in the cabin by the

crew and electronic equipment.

        Humidity can be removed by lowering the air temperature to below the dew point, which

will cause the formation of a condensate film layer. The film layer can then be separated from the

air by means of a slurper that is put into the CHX. The condensate, transported by the air, travels

through the CHX to the slurper holes where it is drained off by negative pressure (Eckart, 212). This

technology can be seen in Figure 2. The condensate is collected and then is transported into a

conditioning tank where it is taken to the waste water tank.

                             Figure 2: Condensing Heat Exchanger and Slurper

       The fans that will be used will require the circulation of the air to be between 0.05 - 0.2 m/s.

They will have HEPA filters installed in front of them so that when the air is pulled through them, it

will be cleansed. They will be able to filter at least 70 microns of particles in the air. The filters,

fans, and CHX will be positioned in duct work which will be located in the ceiling. The filters and

fans will be located on one side of the structure, where they pull in the air that will then pass over the

CHX. Then it moves to the other side of the structure where it is vented back into the habitat. This

can be seen in Figure 3.

                                          Figure 3: CHX Flow Diagram

       The FMF radiators that will be used have been undergoing testing at Johnson Space Center

(JSC). They are comprised of aluminum strips woven together and bonded to stainless steel tubes

which are attached to flexible manifolds at the ends of the radiators. This radiator is very desirable

because it can be rolled into a compact space and opened up upon arrival, which can simplify

delivery and deployment. The flexibility is also advantageous when using the radiator. It can be

bent and formed around desired locations which will help to free up much needed space.

       The FMF radiators were designed to radiate 170 W/m2 at an environment temperature of 155

K, with a radiator inlet temperature of 291 K. The testing that was performed at JSC was not set to

these parameters, but after analyzing the data that was collected, it has been confirmed that the FMF

radiator would have easily exceeded this criteria. The tests that have been performed concluded that

the radiators would exceed the predicted bend radius of 3 inches. It was tested to bend around a

minimum radius of 2.5 inches.

4.0 Waste Management System: Jason Park                                                                  Comment [v17]: Format

       The CEV will utilize a Waste Management System (WMS) similar to the ISS system. The            Comment [v18]: You need to compare systems
                                                                                                      if you are to use an existing one – this may not be
                                                                                                      appropriate for your application
primary difference is that the waste can be processed for used elsewhere. A small amount of water

can be extracted from the waste and sent to the waste water tank for possible regeneration. The

processed solid waste can be used for nutrients in the hydroponics plant system. Any excess solid

waste will be stored and disposed off.

5.0 Sanitation-Managing Housekeeping and Trash: Jason Park

       Cleaning and sanitation is an important consideration that can directly affect the crew. The

total number of wipes each astronaut will use daily are: 3 utensil detergent, 3 utensil rinse, 4

detergent, 1 disinfectant and 8 dry. This amounts to a mass of 0.3 kg/person/day and a volume of

0.002 m^3/person/day to provide the minimum required.

       Table 1 lists the types of waste products that must be managed, including wastes in semi-

solid, solid, or mixed form.

     Waste Category                                  Waste Type
     Biologically decomposable, liquid               Hygiene water, metabolic water,
                                                     respiration/transpiration water, feces
                                                     (liquid part), urine
     Biologically decomposable, solid                Feces (solid Part), waste with bound water,
                                                     solids from urine, sweat and hygiene water,
     Metabolic, gaseous                              CO2, trace gases, methane
     Non-recoverable, liquid                         Products from experiments, medicine
     Non-recoverable, solid                          Spare parts, plastic, metal
                                         Table 1: Waste Products

A trash compactor will be incorporated into the design. This will aid in minimizing the area trash

from food and broken parts will occupy.

6.0 Water Recovery and Supply: Hailey Hartwell                                                        Comment [v19]: Format

       The water supply and regeneration on the CEV will be provided by the AWRS system, which

is shown in Figure 4.

                                        Figure 4: AWRS Schematic

This system regenerates waste water received from the human waste system, the food waste,

thermal condensate, and hygiene waste. The various sources of waste water are sent to the waste

water tank. The waste water tanks feed into the AWRS system. The AWRS system is comprised of

many subsystems. The first two are bioreactors which removed mechanical and organic

contaminants. Next is a reverse osmosis system to remove inorganic contaminants. The water is

further purified using catalytic oxidation and multi filtration. The purified water is tested by the

water processing unit for proper purification levels. If a water test is rejected for purity, the water

will be looped back to the waste water tank to re-enter the AWRS system. The purified water is

conditioned and stored in potable and hygiene water tanks for consumption by the crew. The

potable water tank is accessed by crew for food preparation and drinking. The hygiene water is

distributed to the hygiene, laundry, and waste systems as needed. All systems that sustain life on

board the CEV must have redundancy and warning systems. The AWRS has redundancy by having

three separate filtration and bioreactor systems. Only one system runs at a time, but there is dual

fault tolerance in the system. The parts of AWRS have tested and documented services lives and

have built in monitors for when a part has reached the maximum service life. A control panel alerts

the crew when a part has reached its service life, so it can be replaced.

7.0 Caution and Warning and Fire Detection: Brandon Bethune

7.1 Caution and Warning

       The caution and warning system that will be used is subdivided into three classifications of

circumstances. The first classification, Class 1 (Emergency), is for situations that are time-critical

procedures to correct them. A Class 2 (Caution and Warning) is for any parameters that are out of

limits. A Class 3 (Alert) is for situations leading up to a C/W. A schematic of the caution and

warning classification can be seen in Figure 5.

                                  Figure 5: Caution and Warning Classifications

7.2 Fire Detection and Suppression

       The system that will be used for smoke detection is the TCCS or trace contaminant control

system. It will be equipped with an ionization detection sensor to detect particles of smoke. Other

ionization detection sensors will be located every 25 cubic meters throughout the transit vehicle. If

the concentration of smoke particles exceeds 2000 micrograms or the rate of concentration increases,

then the off nominal data will be sent to the Command and Data Handling System (CDH) to alert the

crew members of a possible fire. Halon 1301 will be used to suppress the fire. Each bottle of Halon

will contain approximately 3.8 pounds of compressed Halon in an 8 inch long cylinder with a radius

of 4.25 inches. They will be place in each corridor of the transit vehicle to allow emergency access.

These extinguishers will also be equipped with a nozzle that will fit a 0.25-0.5 hole required for

each circuit panel to allow access to the volume behind each panel.                                     Comment [v20]: This will allow Halon to get
                                                                                                        into the crew compartment – it can suffocate the
                                                                                                        crew. Halon can be used only in small quantities or
       Fans and HEPA filters will be used to circulate and filter the air of any dust or debris         must be in airtight avionics volumes

throughout the human inhabited portion of the transit vehicle.   The Halon 1301 is dangerous to

humans; however, when taking precautions and little is used the effects are minimal. Halon 1301

must decompose to be effective in suppressing a fire. It starts to decompose the second it is exposed

to a hot surface above 900 degrees Fahrenheit.

       The water mist system consists of a polycarbonate tube that is 52 cm long and 7 cm in

outside diameter with a volume of 1.6 liters. This system minimizes the water droplet sizes while

using the least amount of water to extinguish a fire. A schematic of the water mist system can be

seen in Figure 6.                                                                                       Comment [v21]: This is not technically correct.
                                                                                                        You must not have carefully read the article about
                                                                                                        this. What you have referenced and shown as a fire
                                                                                                        suppression system is in reality an experiment in fire
                                                                                                        suppression. The hardware shown is only to conduct
                                                                                                        combustion suppression experiments, not act as a
                                                                                                        fire suppression system for a spacecraft.

                                 Figure 6: Water Mist System Schematic

8.0 Pressure Control: Ashley McDonald

       The Pressure Control System (PCS) utilized onboard the CEV is the same as the PCS used on

the space shuttle orbiter. The functions of the PCS include: regulation of helium pressure from the    Comment [v22]: You need to compare systems
                                                                                                       if you are to use an existing one – this may not be
                                                                                                       appropriate for your application
helium vessels to the propellant tanks, prevention of backflow of propellant liquid and vapor during

coast phases, health monitoring during ground, flight and orbital phases, and isolation of pressure

before first operation and after station acquisition. It consists of a nitrogen and oxygen control

panel, nitrogen and oxygen supply panel, oxygen partial pressure sensors, cabin positive pressure

relief valves, cabin negative pressure relief valves, and cabin pressure bleed valves. Complementing

the PCS is the Airlock Support Components (ASC). These consist of a pressure gage, an

equalization valve, a depressurization valve, an oxygen supply valve, and an isolation valve.

       The PCS shall normally maintain the cabin partial pressure of oxygen in the range of 2.95 –

3.45 psia. In an emergency situation, the PCS shall maintain the percentage of oxygen concentration

to less than 30 percent. The PCS will provide the capability to purge the cabin air of 95% of

contaminants within one hour.                                                                          Comment [v23]: How? This needs explanation


Advanced Diagnostic Systems for ISS. 2004.


Caution and Warning System. <>

Eckart, p. 1996. Spaceflight Life Support and Biospheres. Dordrecht, The Netherlands:    Kluwer

       Academics Publishers and Torrance, CA: Microcosm Inc.

Funke, H. "Oxygen Generation for Space." 1998. ESA. 4 Nov. 2004


Human Space Flight (The Shuttle). “Caution and Warning System.” April 07, 2002.


Larson, Wiley J. and Linda K. Pranke. Human Spaceflight: Mission Analysis and

       Design. Space Technologies Series

Niu, William. “Atmosphere and Water Quality Monitoring on Space Station Freedom” Long Beach,

       CA. 1990.

"Oxygen regeneration and carbon dioxide removal." Mars Society Education Web. 5 Nov. 2004


Van Bramer, Scott E. "An Introduction to Mass Spectrometry." 1997.

Water Mist Fire-Suppression Experiment. December 2001.



Water Mist Fire-Suppression Experiment (Mist) Studying Fire in the Sky. February 2002.


Appendix 1.0 Air

Appendix 1.1 Atmosphere Monitoring System

                                                        Total Power     Total Volume
                                        Cost ($)       Required (kW)       (m^3)        Total Mass (kg)   Multi-Functional   Reliability    % Error
                    Gas Analyzer       $1 - 4.9 M          0.016         0.0329593            17.3                6              7         < 25-35%                          Comment [v24]: What is the source of this data
   Atmospheric Composition                                                                                                                                                   – it should be referenced or explained
            Monitor                     $150,000          0.03182        0.0370978              10               9               10          <2%
  Central Atmosphere Monitoring
                        System            $1 M            0.03967          0.0454               11.1              8              8           <5%
    Prototype Trace-Gas Monitor           $3 M               3               0.5                 38               8              6          <0.1%
Normalized Values                          10                9                8                   7               5              4            3           2           1
                           Cost          $0-50K          $50-100K        $100-250K          $250-500K         $1-1.5 M        $1.5-2M      $2M-10M    $10-50M    $50-$100M
            Power Required (kW)          0-0.001         .001-.005        .005-.01            .01-.05          .1-.50         .50-0.75     0.75-1.0    1.0-2.0     2.0-5.0
                    Volume (m3)          0-0.001         .001-.005        .005-.01             .01-.1          .1-.25         .25-0.50     0.50-1.0    1.0-2.0     2.0-5.0
                                                                                                                                            100.0-     150.0-     200.0-
                     Mass (kg/p)          0-5.0           5.0-10.0       11.0-20.0            25-35.0        50.0-75.0       75.0-100.0     150.0      200.0       250.0
                             TRL            9                8               7                   6               4               3            2          1           1
                Multi-Functional           10                9               8                   7               5               4            3          2           1
                       Reliability         10                9               8                   7               5               4            3          2           1
                         % Error         <0-1%           <1.1-2.0%       <2.1-4%              <5-10%         <15-24%          <25-39%      <40-49%    <50-99%     <100%
Weighting Factors

                                      Multiplication     Rational
                                                           not as
                             Cost           3            important
             Power Required(kW)             2            important
                    Volume (m3)             5          most important
                     Mass (kg/p)            4          very important
                              TRL           2            important
                 Multi-Functional           4          very important
                        Reliability         4          very important
                          % Error           3            important
                                                                        Atmospheric         Atmosphere
                                        Weighted                        Composition         Monitoring    Prototype Trace-
Calculated Solutions                     Factor        Gas Analyzer       Monitor             System        Gas Monitor
                           Cost            3                 3               7                  5                 3
            Power Required (kW)            2                 7               7                  7                 1
                   Volume (m3)             5                 7               7                  7                 4
                    Mass (kg/p)            4                 7               9                  8                 5
                            TRL            2                10               10                 8                 6
               Multi-Functional            4                 6               9                  8                 8
                      Reliability          4                 7               10                 8                 6
                        % Error            3                 4               9                  7                10
                       TOTAL=                              170              229                197              149
Appendix 1.2 Oxygen Production and Carbon Dioxide Removal

                                                            Comment [v25]: This trade study is not done for
                                                            the mission assigned – I think this was taken from
                                                            the homework which was an entirely different
                                                            mission – therefore it is a bad trade analysis

                                                                        Power Required        Reliability
Specification Sheet    Mass (Kg)              Volume (m³)                   (kW)                 (%)              TRL          Safety
   LiOH canisters        315                     0.225                      0.012                 95               9       Somewhat safe
     Vozdukh              48                      0.7                        0.75                 85               9       Extreme safety
       CDRA               90                     0.45                         0.9                 90               9       Extreme safety
      Sabatier           114                     0.21                        0.06                 95               7       Extreme safety                                                  Comment [v26]: This does not include the 2 bed
                                                                                                                                                                                           sieves you said would be part of your Sabatier
Weighted Factors      Multiplication              Rationale                                                                                                                                system
     Mass                   5          Some budget constraints
                                       Need room for crew and
     Volume                 4          stuff
  Power Required            2          Somewhat important
                                       Not so important on short
     Reliability            2          flight                                                                                                                                              Comment [v27]: This is not a short flight
       TRL                  1          All pretty much developed
      Safety                1          All relatively safe

 Normalized value          10                      9                           8                  7                 6            5                4          3              2       1
       Mass                                                                                                                                                                        315-
        (kg)              0-35                   35-70                       70-105            105-140        140-175         175-210          210-245    245-280      280-315     350
        (m³)              0-.08                  .08-.16                     .16-.24           .24-.32            .32-.4       .4-.48          .48-.56     .56-.64     .64-.72    .72-.8
  Power Required
       (kW)               0-.1                   .1-.2                        .2-.3              .3-.4            .4-.5        .5-.6             .6-.7      .7-.8       .8-.9     .9-1.0
  Reliability (%)        95-100                  90-95                       85-90              80-85             75-80        70-75            65-70      60-65        55-60     50-55
       TRL                 9                       8                            7                  6                5            4                 3          2           1         1
                        Complete                                                                             Some what                                                  Very
       Safety            safety              Extreme safety                 Very safe            Safe          safe            Risky           Mod risk   High risk   high risk   Unsafe

                                                           LiOH canisters                               Vozdukh                         CDRA                     Sabatier
    Solutions           Wt factor             Norm Value                      Total       Norm Value              Total     Norm Value          Total      Value        Total
      Mass                  5                     2                            10              9                   45           8                40          7           35
     Volume                 4                     8                            32              2                   8            5                20          8           40
  Power Required            2                     10                           20              3                   6            2                 4         10           20
    Reliability             2                     10                           20              7                   14           8                16          9           18
      TRL                   1                     10                           10             10                   10           10               10          8            8
     Safety                 1                     6                             6              9                   9            9                 9          9            9
                                                              Sum =            98                                  92                            99                      130

Appendix 2.0 Food

Appendix 2.1 Food Type Trade Study

Specification Sheet    Hydroponics        Carry-on      Combination
Mass (kg)                 2200             1863           1896.7
Volume (m^3)               81               6.48          13.932
Power Required
(kW)                       18.9           8.10701        9.186309
TRL                         7                9                9
Launch Cost ($B)          0.528           0.44712        0.455208
Reliability (%)             75              100              95
Variety                  Very little      Moderate       Very much

Normalized Value             10              9                8              7              6              5             4           3              2            1
Mass (kg)                  0-220          220-440          440-660        660-880       880-1100       1100-1320    1320-1540   1540-1760      1760-1980     1980-2200
Volume (m^3)               0-8.1          8.1-16.2        16.2-24.3      24.3-32.4      32.4-40.5      40.5-48.6    48.6-56.7    56.7-64.8      64.8-72.9     72.9-81
Power Required                                                                                                        11.34-
(kW)                      0-1.89          1.89-3.78       3.78-5.67      5.67-7.56      7.56-9.45      9.45-11.34      13.23    13.23-15.12    15.12-17.01   17.01-18.9
TRL                         9                 8               7              6              5               4            3           2              1            1
                                           0.0528-         0.1056-        0.1584-        0.2112-         0.264-      0.3168-      0.3696-        0.4224-      0.4752-
Launch Cost ($B)         0-0.0528          0.1056          0.1584         0.2112          0.264          0.3168       0.3696      0.4224         0.4752        0.528
Reliability (%)           90-100            80-90           70-80          60-70          50-60          40-50        30-40        20-30          20-10         0-10
                                           Almost                                                                                                Almost
Variety                  Extreme          Extreme        Very much          A lot       Moderate         Some         Little     Very little      none         None

                       Multiplication     Rationale
Mass (kg)                    4          The less mass, more money saved
Volume (m^3)                 3          The less volume, more space for experiments and life support
Power Required
(kW)                         3          Less power required, more power saved for other operations
TRL                          2          Matters, need the technology now
Launch Cost (M$)             2          Budget Constraints
Reliability (%)              4          Very important; need the crew to stay alive
Variety                      2          Don't want crew to be bored and lose spirits

                                                  Hydroponics                   Carry-on                    Combination
                          Weight                                           Norm
                          Factor        Norm Value          Total          Value         Total         Norm Value     Total
Mass (kg)                   4               1                4               2            8                2            8
Volume (m^3)                3               1                3              10            30               9           27
Power Required
(kW)                         3                1                  3            6             18             6          18
TRL                          2                8                 16           10             20            10          20
Launch Cost                  2                1                  2            2             4              2           4
Reliability (%)              4                8                 32           10             40            10          40
Variety                      2                3                  6            6             12             8          16
         Grand Total                                            66                         132                        133

Appendix 2.2 Plant Type Trade Study

                         Required                                            Max Crop
     Plant Type            Light        Temperature       Humidity            Growth           Plant Volume
                       (mol m-2g-1)      (Celcius)        (% Rh)           [g/(m2 day)]            (m3)
      Broccoli            250-275           22-28           50-85               30-40            0.003375
       Carrots            275-400           15-25           50-70               30-40            0.000375
       Lettuce            250-275           22-28           50-85               20-30            0.003375
     Sunflowers           250-275           22-28           50-85               20-30            0.003375
       Tomato             300-400           20-28           50-75               30-40              0.027
       Alfalfa           0-ambient          20-28          High-90              20-30              0.0005
        Bean             0-ambient          20-28          High-90              20-30              0.0005
  Normalized Value           5                 4              3                   2                   1
   Required Light           0-80           80-160          160-240            240-320             320-400
    Temperature           12.8-35         35-51.25        51.25-67.5         67.5-83.75          83.75-100
      (Celcius)           12.8-35          9.6-12.8        6.4-9.6             3.2-6.4              0-3.2
      Humidity             30-70           70-77.4         77.4-85            85-92.5             92.5-100
       (% Rh)              30-70           22.5-30         15-22.5             7.5-15               0-7.5
Max Crop Growth Rate       40-50            30-40           20-30               10-20               0-10
    Plant Volume         0-0.0054           0.0108      0.0108-0.0162     0.0162-0.0216        0.0216-0.027
                       Multiplication     Rationale
   Required Light            1          The less light, the more power saved
    Temperature              1          The closer to habitat temperature, more power saved
      Humidity               1          The closer to habitat humidity, more power saved
Max Crop Growth Rate         3          The larger crop growth, the more available food
    Plant Volume             2          The less volume, more available space and less money

                                          Broccoli                            Carrots                         Lettuce           Sunflowers
                                                                                                               Norm               Norm
                          Weight        Norm Value          Total          Norm Value             Total        Value    Total     Value      Total
   Required Light           1               2                 2                1                    1            2       2           2        2
    Temperature             1               5                 5                5                    5            5       5           5        5
      Humidity              1               3                 3                5                    5            3       3           3        3
Max Crop Growth Rate        3               4                12                4                   12            3       9           3        9
    Plant Volume            2               5                10                5                   10            5       10          5        10
     Grand Total                                             32                                    33                    29                   29
                                          Tomato                              Alfalfa                         Bean
                                        Norm Value          Total          Norm Value             Total       Value     Total
   Required Light            1              1                 1                5                    5           5        5
    Temperature              1              5                 5                5                    5           5        5
      Humidity               1              4                 4                1                    1           1        1
Max Crop Growth Rate         3              4                12                3                    9           3        9
    Plant Volume             2              1                 2                5                   10           5        10
     Grand Total                                             24                                    30                    30
Appendix 2.3 Menus

                     Comment [v28]: Where does this come from –
                     does it include your grown plants? Need to

Twenty Day Meal Plan

Day 1                  Day 2          Day 3

 Day 4                   Day 5        Day 6

 Day 7    Day 8         Day 9

Day 10   Day 11        Day 12

 Day 13            Day 14             Day 15

Day 16    Day 17            Day 18

Day 19   Day 20

Appendix 4.0 Waste Management System

Specification Sheet           Shuttle              ISS
System Mass                              45                  45
Supplies Mass                         226.8               226.8
System Volume                          2.18                2.18
Supplies Volume                       1.701               1.296                                                                                              Comment [v29]: This is not correct data – the
TRL                                       9                   9                                                                                              systems are not the same.
AccomodationAccommodation               No                  Yes

     Normalzied Value            10                  9               8         7              6         5           4           3         2         1
                                                                     20.0-                                                      70.0-     80.0-     90.0-
System Mass                    0.00-10.0            10.0-20.0         30.0   30.0-40.0   40.0-50.0   50.0-60.0   60.0-70.0       80.0      90.0     100.0
                                                                      100-                                                                 400-
Supplies Mass                      0-50                  50-100        150    150-200     200-250     250-300     300-350    350-400        450   450-500
System Volume                     0-0.5                  0.5-1.0   1.0-1.5     1.5-2.0     2.0-2.5     2.5-3.0     3.0-3.5    3.5-4.0   4.0-4.5    4.5-5.0
Supplies Volume                   0-0.5                  0.5-1.0   1.0-1.5     1.5-2.0     2.0-2.5     2.5-3.0     3.0-3.5    3.5-4.0   4.5-5.0    5.0-5.5
TRL                                  10                        9         8           7           6           5           4          3         2          1   Comment [v30]: We have no 10 in our TRL
Connection Accomodation        Complete                                                                                                              None    system

Weighted Factors            Multiplication       Rationale
System Mass                       4           Very Important
Supplies Mass                     4           Very Important
System Volume                     4           Very Important
Supplies Volume                   4           Very Important
TRL                               3           Matters
Connection                                    Not too
AccomodationAccommodation         2           Important

                                                 Shuttle                      ISS
                            Weight                                           Norm
Calculated Solution         Factor             Norm Value          Total     Value        Total
System Mass                      4                 6                24         6           24
Supplies Mass                    4                 6                24         6           24
System Volume                    4                 6                24         6           24
Supplies Volume                  4                 7                28         8           32
TRL                              3                 9                27         9           27
AccomodationAccommodation         2                  1               2         10           20
Grand Total                                                         129                    151

Appendix 6.0 Water Recovery and Supply

Specification Sheet
                                                          Vol. system                                                                    Cost        Cost Launch (to
                       Mass H2O        Mass System          (m^3)            Vol. Stored     Power         TRL        Recovery Eff.     system            LEO)
CWP                     11525.76               110                   0.6           11.53      0.125              9             0.2          2.2 M            230.52M
AWRS                     2613.79               150                   0.8              2.6      0.18              7            0.85            3M              52.28M
Stored                   14407.2                 0                     0           14.41           0             9                0             0           288.14 M    Comment [v31]: Too low numbers – for a 270
Weighing Factors                                                                                                                                                        day mission using all the water you plan for with
                      Multiplication     Rationale                                                                                                                      dish and clothes washing (25kg/p/d according to
                                       Mass is limited and very                                                                                                         Larsen) that is 20,250 kg
Mass H2O                    4          important
                                       Mass is limited and very
Mass System                 4          important
Vol. system (m^3)           2          Important but not critical
Vol. Stored                 2          Important but not critical
Power                       1          Nuclear power source means not strictly limited
                                       Needs to be available by 10
TRL                         1          years
Recovery Efficiency         4          Must be regenerative to be in mass requirement
Cost system                 3          Budget is limited and important
Cost Launch                 3          Not in ECLSS budget, but a factor to the project as a whole
Parameters                                                                                                                                                              Comment [v32]: What are each of the
10                          9                8                 7                  6           5             4              3              2                1            normalized parameters and their units? You left off
                                                                                              7500-         9000-                         12000-                        a column of the table
0-1500                  1500-3000        3000-4500            4500-6000      6000-7500         9000         10500     10500-12000          13500        13500-15000
0-25                        25-50            50-75               75-100        100-175      175-250       250-300         300-350        350-400              400 +
0-.2                         .2-.4            .4-.6                .6-.8         .8-1.0         1.0+
0-2                        2.0-4.0          4.0-6.0              6.0-8.0        8.0-10.0        12.0     12.0-14.0        14.0-16.0    16.0 - 18.0        18.0 - 20.0
0-.1                          .1-.2             .2-.3                .3-.4          .4-.5       .5-.6         .6-.7            .7-.8
9                                 8                 7                    6              5           4             3                2             1                  0
1                          .99-.96            .95-.9               .9-.85          .84-.8       .8-.7         .7-.6            .6-.3         .3-.1                  0
.5M                          1-3M              3-6M               6-10M              10M
1-20M                      20-50M           50-55M              55-60M           60-80M     80-100M      100-125M        125-150M      150-200M                200M +
Calculated Values                                            CWP                             AWRS                          Stored
                      Multiplication    Normalized           Total           Normalized       Total     Normalized       Total
Mass H2O                           4              3                    12             9           36             1              4
Mass System                        4              6                    24             6           24             0              0
Vol. system (m^3)                  2              8                    16             7           14            10             20
Vol. Stored                        2              5                    10             9           18             4              8                                       Comment [v33]: This is not correct for stored
Power                              1              9                      9            9             9           10             10                                       water - there is no need to recover any so the
TRL                                1             10                    10             9             9           10             10                                       efficiency should be 100% to not penalize this
Recovery Efficiency                4              2                      8            7           28             0              0
Cost system                        3              9                    27             9           27             0              0                                       Comment [v34]: You don’t have a cost so you
Cost Launch                        3              1                      3            8           24             1              3                                       cannot say zero for the normalized value – it
                                                                                                                                                                        penalizes this method because you did not complete
                                            Sum =                     119                        189                           55                                       your spec sheet.
Appendix 10 ECLSS Documents

Appendix 10.1 ECLSS Mass and Volume Budget

Air Systems                          Volume (m^3)     Mass      Comment [v35]: This is a good addition – it
Sabatier: Co2 Removal                         0.28      17.9    doesn’t match the text exactly but is still a good idea.
Electrolysis: Co2 to 02 (GCSA)                0.29       130
BMS - 2                                       0.26      48.1
Oxygen tanks                                 0.642      1650
Nitrgoen Tanks                               1.926      4950
Atmosphere Monitoring System                0.0379        10
Hepa Filters (1 per 5m^3)                     0.15      31.5
Fans (1 per 5 m^3)                           0.099        45
Heat Exchanger                                0.14        44
TCCS                                          0.45        60
Smoke Detectors (1per 25 m^3)               0.0165         5
Halon Extinguishers( 1 per 15 m^3)        0.07439       17.2
Food Systems
Food and Packaging                           5.832     1676.7
Sink                                        0.0135         15
Freezer                                       0.75        150
Microwave                                      0.6        140
Cooking and Eating Supplies                 0.0042         15
Kitchen Supplies(sponges/soap)               0.162       22.5
Growing System                                 8.1       220
Waste Management
Waste System (Toliet)                         4.36        90
Supplies                                     0.567      226.8
Shower                                        1.41         75
Sink (hand/face wash)                         0.01          8
Hygiene kits                                 0.015        5.5
Supplies                                      1.21      20.25
Clothing                                       1.2       297
Washing Machine                               0.75       100
Dryer                                         0.75        60
Vacuum                                        0.07         13
Cleaning wipes                                 1.5        1.5
Trash Compactor                                0.3        150
Trash bags                                     0.6       40.5
Sleep Accommodations
Bed Areas                                     0.45        27
Crew Health Care
Exercise Equipment                            0.19       145
Medical/Surgical/ Dental Suite                   4       500
Medical/Surgical Consumables                  1.25       225
Water System
Stored Water Space total                       2.8      2800
Water Recovery System                            1       100
Tools and Accessories                            1       300
Test Equip/ Spare parts                        1.5       500
Operational Supplies                         0.008        60
Living Areas
Kitchen Space                                  3.5         0
Bedroom Space                                    9         0
Exercise/ Recreation Space                     4.5         0
Sums:                                     61.76749   14992.45

Appendix 10.2 ECLSS Diagram

                              Comment [v36]: This ia a nice summary

Appendix 10.3 Habitat Schematic

     Comment [v37]: This drawing could use much
     more detail – i.e. the location and layout of the many
     systems (not just yours but all the others like EPS,
     TCS, DPS, GNC, etc) as well as the location of
     stowed items . With the actual volume required
     including spacing around equipment, I think you
     would have found that you would have little room
     for the crew.


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