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Engineering Science Contexts and Challenges Education Scotland

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					engineering



          Engineering Contexts and Challenges
        Renewable Energies: Biomass Generation
The Engineering Scenario: Biomass Energy Generation   slides 2-3
The Main Branches of Engineering                      slide 4
The Systems Approach                                  slides 5 -7
Making Biogas / Energy Transformations / Mechanisms   slides 8-9
Modelling solutions                                   slide 10
Energy generation systems                             slide 11-14
Presentation                                          slide 15


Biogas Generator Extension Work                       slides 16-
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The Engineering Scenario.

A Scottish based distillery company plans to install a biomass generator that produces
energy by burning the large amount of used grain (waste) produced in the distilling
process. They want to build the biomass plant on their existing site.

Many companies are considering using renewable means to generate energy. The main
reasons for this are:

• to comply with laws and regulations meant to help the environment
• to improve the company’s reputation by showing they are a responsible company and
  environmentally friendly
• to save money by not having to buy electricity or generate electricity by other less
  environmentally friendly means
• to make their energy supply reliable and reuse cheap and available materials

Activity. Find out about biomass generation and, through discussion, suggest other
advantages of using this form of energy generation.
  engineering


In this activity we will consider some of the engineering tasks and activities required to
build an engineering ‘plant’ of this type. Once we understand how the systems work we
will design and ‘model ‘some of the systems necessary to create movement and produce
or convert energy.

Activities.
Through group and class discussion, internet research and, where possible, by discussion
with practicing engineers.
1. identify the:
    • main branches of engineering likely to be involved in building this plant.
    • ‘types’ of engineer responsible for each of these stages: the planning, designing,
       construction, testing and maintenance of the new plant
2. Biofuel and biomass are forms of renewable energy generation. List four types of
    renewable energy sources and three fossil fuels used in electricity generation and
    comment on the environmental implications of each.

The main branches of engineering are shown in the following slide.
Examples of engineering sub branches are included on separate slides 18-23.
engineering



An Application of Science,                                     Main Branches of
    Mathematics and                                              Engineering
       Technology                                                  Mechanical
                                                                   Engineering


                                                                      Civil
              Engineering                                          Engineering


                                                                    Electrical
                                                                   Engineering
        Engineering is a combination
    between the abstract of science and
     the beauty of art (Martin Bercovici)                           Chemical
                                                                   Engineering

Activity. Consider one ‘main branch’ of engineering and the note some of the most important activities
and products involved. Other engineering sub branches are included on slides18-23.
   engineering


The Systems Approach

Large engineering projects such as the biomass generator are complex. To make them easer
to understand a Systems Approach is used. One feature of the systems approach is to use:
         Input     >>                  process            >>       output
(what goes in) > (what happens inside the machine for example) > (what comes out)

From the overall system diagram engineers can then decide what sub-systems will deal with
each of the inputs and which will produce each of the required outputs. This gives a clearer
picture of what the complete system will look like including how the sub-systems are
connected together.

Activity. For a simple system, such as the kettle – identify the inputs, processes and output.

The next slide shows some of the important inputs and outputs of the distillery.
Activity. By discussing the main inputs and outputs identify some of the possible
environmental impacts from such a plant.
Supplementary questions on environment issues are included in extension slide 17.
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              System Diagram




                               Activity. By discussing the main
                               inputs and outputs identify some
                               of the possible environmental
                               impacts from this plant.
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Sub-system diagram showing biomass energy generation



   Super grain
  feed hopper             Belt presses
                                                                  Used grain
                                 Grain                            (waste)
                                 cake

   Anaerobic     Biogas     Bio fuel              Steam    Electricity
                                                                         Distillery
    Digester                 Boiler              Turbine



                                                                Export electricity
 Natural gas              Existing       Steam
                          Boilers
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Making Biogas. The video clip           How it Works – Making Biogas
shows how biogas is produced. The
movement of the products around
the system is controlled by various
mechanisms.
Activity: watch the clip and identify
mechanisms used in this system.
Mechanisms are used to open and
close the gates and valves to allow
the products to flow from one part
of the system to another. The gate
in the Shed is opened using an
electric motor, which is connected
to a mechanism known as a rack
and pinion. Mechanisms change
the size and direction of force
produced at the output of the
mechanism compared to the input
force.
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• Mechanisms can also covert one type of motion to another.
• Electric motors produce what is known as rotary motion at their output shaft. As
  you saw in the video clip the gate has to move in a straight line up and down.
  Motion in a straight line is called linear motion and straight line motion which
  repeats over and over is known as reciprocating motion. Types of Motion

• The system diagram for a rack and pinion mechanism is shown below. This
  mechanism converts rotary motion to linear reciprocating motion.




This example of a control is shown as a simulation model in the slide 10.
Activity Extensions.
1. A number of other modelling challenges of control systems, based on the Biogas
    Generator , can be found in the extension materials. Slides 24-27.
2. Study the mechanisms in a bicycle and explain how motion is converted.
   engineering



Electronic simulation software ,such
as YENKA as shown here, allows
mechanisms and electrical circuits to
be combined and the resulting
system simulated.

Activity: Shed Gate control.

1. Draw up a sub-system diagram
   for the system shown for
   opening and closing the shed
   gate.

2. Build the circuit shown using
   suitable electronic simulation
   circuit software.
  engineering




The video clip shows how
                             How it Works - Biogas Plant
grain, and other materials
can be used to produce
biogas.
Activity
How many examples of
rotary motion converted
to linear motion, or vice
versa, are shown in the
video clip?
Activity Extension. A
number of other
modelling challenges can
be found in the extension
materials. Slides 25-27.
 engineering



Activity                  How it Works - Micro-hydro Process
Watch each of the
following three videos.
1. Micro-hydro power
2. Wave Power
3. Combined heat and
    power plant

Choose one to discuss
in more detail and
then draw up a sub-
system diagram
showing the energy
transformations in the
process.
 engineering



                          How it Works - Wave Power Process
Activity

Choose one
video/audio clip to
discuss in more detail
and then draw up a
sub-system diagram
showing the energy
transformations in the
process.

For background to
energy generation from
the ocean please click.
  engineering



Activity                   How it Works - Heat and Power Process

Choose one video/audio
clip to discuss in more
detail and then draw up
a sub-system diagram
showing the energy
transformations in the
process.

Extension Activity. Find
out how a steam
turbine works and
compare its complexity
to a wind turbine or
tidal power turbine.
  engineering


                                      Presentation

Prepare a presentation which demonstrates your understanding of the importance of
engineers to society.

The presentation should last around 5 minutes.

The presentation could be based on a historical contribution made by engineering, a
current product or project, or a future development.

 • A historical contribution could be a description of an invention or inventor, or a civil
   engineering project from the pyramids to castles, roads, bridges and so on.

 • A current contribution should focus on the role of one particular engineer in the
   development of an important product or project.

 • A future contribution should look at how an emerging technology could be developed
   to provide benefits to individuals or society as a whole.
engineering



             Engineering Contexts and Challenges

       Extension work based on the Biogas Generator


The social and environmental impact of engineering   slide 17

Engineering Sub Branches                             slides 18-23

Systems Modelling                                    slides 24-27
  engineering



         The social and environmental impact of engineering.
Activity
There are many benefits for the distillery company from the biomass project. List four of
these benefits and explain them.

This project would help to reduce the need for energy generated from finite (fossil fuel)
sources. What benefits would a power generation plant of this type have for society as a
whole?

The project would also have some advantages and disadvantages to the local community,
especially those living close to the plant.
• What social and economic benefits would the project bring to the local community?
• What disadvantages would there be for those living around the plant, both during the
  building phase and afterwards?
• In terms of the health and wellbeing of society - discuss the pros and cons of
  supporting a company that produces alcohol?
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              Engineering Sub- branches


   • Mechanical Engineering           slide 19
   • Civil Engineering                slide 20
   • Electrical Engineering           slide 21
   • Chemical Engineering             slide 22
   • Hybrid Engineering               slide 23
     engineering




                                              Mechanical
                                              Engineering


Vehicle Engineering
                                                         Aerospace Engineering           Acoustic Engineering
Design and manufacture of   Thermal Engineering
  devices and systems                                   Design and manufacture of air       The generation or
                            The heating or cooling of                                    suppression of sound and
 which control and propel   processes, equipment, or           and spacecraft
         vehicles                                                                                vibration
                                enclosed spaces
                                                           Specialities include
 Specialities include
                                                        Aeronautical and astronautical
 Automotive, railway and                                        engineering
    naval engineering




      Activity:
      Which of these sub branches could be involved in the Biomass Project and what would be their role?
  engineering




                                                          Civil
                                                Engineering


    Geotechnical                                                                               Environmental
    Engineering                                                      Transport                  Engineering
                                   Structural
Dealing with geological           Engineering                       Engineering             Planning and advising on
materials at the site of a                                                                Improving and protecting the
                             Developing structures that           The manufacture of      environment within a project
civil engineering project         support loads                       molecules

                                                                                            Specialities include
Specialities include         Specialities include             Specialities include
                                                                                           Fire protection, sewage,
  Mining engineering         Earthquake, wind, ocean          Traffic, road and railway   water, waste management,
                                 and architectural                   engineering          and transport engineering
                                   engineering




    Activity:
    Which of these sub branches could be involved in the Biomass Project and what would be their role?
  engineering




                                           Electrical
                                          Engineering

   Electronic Engineering                                                          Power Engineering
                                            Computer Engineering
Design of analogue and digital circuits                                         The generation and delivery of
                                                                             electricity and the design of devices
                                                                              such as motors and transformers
                                          The design of and application of
     Specialities include                     computer systems and
 Control and Telecommunications                  microcontrollers
           engineering
                                             Specialities include
                                           Software engineering, control,
                                               Robotics, networking




   Activity:
   Which of these sub branches could be involved in the Biomass Project and what would be their role?
  engineering




                                          Chemical
                                         Engineering

    Materials Engineering                                                      Molecular Engineering
Using the properties of matter within       Process Engineering
                                                                              The manufacture of molecules
     engineering applications           The design, function and control of
                                              chemical processes
                                                                                 Specialities include
      Specialities include
                                             Specialities include             Petroleum refinery, plastics and
 Ceramic and Chrystal engineering                                                    paper engineering
                                         Petroleum refinery, plastics and
                                                paper engineering




  Activity:
  Which of these sub branches could be involved in the Biomass Project and what would be their role?
engineering




 There are many others, including industrial engineering, nuclear engineering, agricultural
 engineering and applied engineering.


Activity:
Which of these sub branches could be involved in the Biomass Project and what would be their role?
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                         Systems Modelling

 The following ‘modelled’ examples are based on the systems, controls
 and mechanisms found in the Biomass generator and similar engineering
 systems.

 • Grain filling warning system.                             Slide 25
 • Grain hopper sensing system.                              Slide 26
 • Temperature sensing system.                               Slide 27

 Activity. Using appropriate modelling systems and or boards: design,
 assemble, test and evaluate your solutions.
  engineering



Challenge: Grain filling
warning system.
1.Design a system which
  will light a red LED while
  the substrate tank is
  filling. Once a float
  switch detects that the
  tank is full a solenoid
  should close the filler
  pipe and the red LED
  should go off.
2.Draw a system diagram
3.Draw a sub-system
  diagram
4.Build and test the
  simulated circuit shown.
   engineering


Challenge: Grain hopper
sensing system.
1.Design a system that will
  spin a mixing paddle once
  a light sensor detects it is
  dark (showing that the
  grain tank is full) or when
  a test switch is pressed.
2.Draw a system diagram
3.Draw a sub-system
  diagram
4.Build and test the
  simulated circuit shown.
5.Suggest other uses for
  this type of system.
  engineering


 Challenge. Temperature
 sensing system.
1. Design a system that will
   switch on a heater
   (simulated by a lamp)
   when the temperature in
   the fermenting tank falls
   and the heater switch is
   on.
2. Draw a system diagram
3. Draw a sub-system
   diagram
4. Build and test the
   simulated circuit shown.
5. Comment on the success
   of the design and suggest
   other uses for this type of
   system.

				
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