Polar Shelters by z9Oo6YTo

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									            STEM




 An Arctic Solar Shelter
  Design Challenge
          Integrating the
  Engineering Design Process
into a study of the Arctic Region
Kotzebue, Alaska is located 33 miles
     north of the Arctic Circle




 You can learn more about Kotzebue
      by visiting their web site.
        http://kotzpdweb.tripod.com/city/index.html
Students in that community attend
the Kotzebue Middle/High School




    Visit the school’s web site at:
     http://www.nwarctic.org/Schools/kmhs/index.htm
       20 days of sunlight
 Because Kotzebue is just north of the
Arctic Circle, there are 20 days each year
when there are 24 hours of daylight.
 The summer solstice is in the middle of that
20 day period.
  Would it be possible to take advantage of
that 24 hours of sunlight to heat a shelter for
Arctic researchers?
    The Arctic Solar Challenge
       Design, build, and evaluate
    the performance of a portable,
    temporary, passive solar
    structure that can be used as a
    shelter for researchers who will
    be in Kotzebue, Alaska around
    the time of a summer solstice.
.
    In the Arctic Region, there is an interesting
“window of opportunity” for a passive solar collector
     in terms the number of hours of daytime.




 http://www.eoearth.org/article/Earth-Sun_relationships_and_insolation
    Materials you can use to build a
    model of a solar shelter include:
•   A photocopier paper box
•   Transparent window material
•   Reflective Foil
•   Paper of different colors
•   Scissors
•   Insulating Materials
•   Other Easily Obtained Materials
    The Engineering Design Cycle is one way to describe
    the process of designing, building, and evaluating the
      performance of a model of an Arctic solar shelter.
Page 84 of the Massachusetts Science and Technology/Engineering Framework
Designing and building a passive solar shelter
  provides an opportunity to evaluate how
   energy is transmitted and transformed.

• Visible light and near infrared energy
  radiates from the sun and passes though
  windows of a passive solar collector and can
  be transformed into heat (thermal energy).
• Heat is conducted through the walls of a
  structure from a warmer environment to a
  colder environment.
• Convection currents will form as air inside a
  building expands and rises as it is heated or
  compresses and sinks as it cools.
You can design the location of windows so that
 the maximum amount of sunlight enters the
     structure and is converted into heat.

                      .
   Insulating materials selected for your model of a
shelter will reduce the loss of heat by conduction. The
value of those materials depend on
    The thickness of the insulating material
    The type of insulating material
    Strategies used to insulate windows when there is
little or no solar gain




                    T2                               T1




       http://sol.sci.uop.edu/~jfalward/heattransfer/heattransfer.html
     Even igloos have insulated walls.
Air spaces in the blocks of snow reduce
 the reduce the rate at which energy is
      conducted though the walls.




          http://en.wikipedia.org/wiki/Igloo
  You also need to manage the flow of air into
and out of your model of a polar solar shelter.




      http://www.azsolarcenter.com/technology/pas-3.html
Some igloos are built to manage convection!
Entryways of many igloos are designed to be
   lower that the elevated sleeping area.




         http://en.wikipedia.org/wiki/Igloo
       Design a Valid Test.

 You need to simulate the conditions
that polar researchers experience in
Kotzebue, Alaska when you collect
data with your model of a Arctic solar
collector.
For today’s weather in Kotzebue visit:
  http://www.wunderground.com/US/AK/Kotzebue.html
 The angle of incidence of sunlight
  is one factor to consider when
designing a fair test of your Arctic
          solar collector.
  The maximum angle of incidence
of sunlight entering your passive
solar collector needs to be similar
to the maximum angle of incidence
of sunlight in Kotzebue.
    The midday sun in Kotzebue
       The highest altitude of the sun in Kotzebue on the
     first day of summer is 46.5º.




     The U.S. Naval Observatory web site provides
        the sun’s altitude data for any location.
.

              http://aa.usno.navy.mil/data/docs/AltAz.php
    The midday altitude of the sun is also
    approximately 46º F on the following
      dates at the following locations.

• In Corpus Christie, TX on February 5th
• In Charlotte, NC and Flagstaff, AZ on
  February 27th
• In Columbia, MO on March 7th
• In New York City and Redding, CA on March
  12th
• In Detroit, MI and Boston, MA on March 17th
      These dates would occur during a time
    periods when a test of a design of a polar
    solar shelter could be conducted.
.
   Average daily temperatures are also an
    important factor when evaluating the
performance of a model Arctic solar shelter.


  Between the summer solstice and the
middle of August, average high temperatures
in Kotzebue range from 50º F to 60º F. The
daily low temperatures range from 30º F to
50º F.
A NOAA web site can be used to compare early
  summer temperatures in Kotzebue with
 other locations at other times of the year.




     http://www.cdc.noaa.gov/USclimate/states.fast.html
  This web site provides an animation that can
 be used to evaluate how the “sunshine factor”
   affects the window of opportunity for using
 a passive solar collector in the Arctic Region.




http://www.fao.org/WAICENT/FAOINFO/SUSTDEV/EIdirect/climate/EIsp0002.htm
       Other factors to consider when
    determining the fairness of the test
    of the performance of a model of an
         Arctic solar shelter include:

•    Topography
•    Wind direction and speed
•    Ground temperature
•    Any other factors?
Lower Latitude applications of designing
 a passive solar Arctic shelter include:
• Describing how the Arctic shelter
  design can be adapted for use in your
  region in either cooling or heating
  seasons.
• Determining the passive solar potential
  of your school building.
• Evaluating the advantages and
  limitations of passive solar structures.

								
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