# Thermos Challenge

Procedures:

1. Fill a beaker with 150ml of water and set on a hot plate until it reaches a temperature of 100°C
2. Once it reaches 100°C, use tongs to pour the heated water into the thermos and measure the temperature of water after you have poured it into your thermos.
3. Screw on the lid as quickly as possible
4. After 15 mins, take the lid off and check the water’s temperature. Record quantitative and qualitative data.
5. Discuss the successes and improvements that are needed to improve the thermos
6. Create a second prototype based on your conclusions

**From prototypes #1-6, we measured the temperature of the water before we poured it into our prototypes rather than measuring it after we poured it into our prototypes which may have affected our results because heat would be lost during the pour therefore affecting our qualitative results. **

Data:

Prototype #1

 Material Thermal Conductivity Quantity Cost Large Styrofoam cup 0.03 1 \$0.85 Rubber Balloon 0.13 1 \$0.25 Glass jar with lid 1.0 1 \$0.80 Aluminum foil 250 20 sq. inch \$1.00

Total cost: \$2.90

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 98 degrees C 67    degrees C 31 degrees C

QUALITATIVE RESULTS

• Water leaked through the Styrofoam cup
• The lid of the jar was hot
• Glass jar was cloudy and foggy

PROS:

• The glass jar acted as a very good insulator, keeping the heat that escaped the Styrofoam cup in by the heat bouncing off of it.
• The Styrofoam cup was also a good insulator that did not allow heat to pass through easily.
• In the budget

CONS:

• The water leaked through the Styrofoam cup
• Lost a lot of heat through the lid (the jar was not that hot, but the lid became very hot)
• We lost more than 25 degrees of heat in our final temperature
• No design
• Aluminum foil did not do much because of high thermal conductivity.

PROGRESSION:

• We should switch out the aluminum for a material that has a lower thermal conductivity so that energy cannot easily transfer through.
• Change material on lid because that was where we lost most of our heat
• Add design/decorative things to our product so that it is more appealing to the audience.

Prototype #2

 Material Thermal Conductivity Quantity Cost Glass jar with lid 1.0 1 \$0.80 neoprene Sleeve 0.1 1 \$0.85 Foam (pro-wrap) 0.02 1 metre \$0.30 Rubber glove 0.6 1 \$0.25

Total cost: \$2.20

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 97 Degrees C 61 Degrees C 36 degrees C

QUALITATIVE RESULTS

• Glass jar was hot
• Water did not leak

PROS:

• We lost less heat at the top when we used the rubber glove because it has a smaller thermal conductivity than the aluminum foil that we used in the first prototype.
• The water did not leak
• Prototype was in the budget

CONS:

• We lost heat at the bottom of the jar because it was not covered with any material
• We lost heat from the glass jar as well; it was very hot
• We lost more than 30 degrees Celsius of heat

PROGRESSION:

• Substitute glass jar with Styrofoam cup to hold water because it is a better insulator, or possibly use both the Styrofoam cup and glass jar so it can act as a vacuum seal
• Change the lid so that less heat escapes from the top of the jar
• Change the lid so that less heat escapes from the top of the jar

Prototype #3

 Material Thermal Conductivity Quantity Cost Small Styrofoam cup 0.03 1 \$0.75 Neoprene Sleeve 0.1 1 \$0.85 Foam (pro-wrap) 0.02 1 metre \$0.30 Rubber glove 0.6 1 \$0.25 Glass jar with lid 1.0 1 \$0.80

Total cost: \$2.95

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 99 Degrees C n/a n/a

QUALITATIVE RESULTS

• PROTOTYPE COULD NOT HOLD 150 ML OF WATER

PROS:

• In the budget

CONS:

• Could not hold 150 ml of water

PROGRESSION:

• Make sure that our prototype is large enough to hold the amount of water.

Prototype #4

 Material Thermal Conductivity Quantity Cost Glass jar with lid 1.0 1 \$0.80 Neoprene Sleeve 0.1 1 \$0.85 Foam (pro-wrap) 0.02 1 metre \$0.30 Small Styrofoam cup 0.03 1 \$0.75 Rubber glove 0.6 1 \$0.25

Total cost: \$2.95

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 99 degrees C 68 degrees C 31 degrees C

QUALITATIVE RESULTS

PROS:

• The rubber glove covering the top of the jar and acting as the lid was a good vacuum seal.
• Styrofoam inside of the glass acted as a good insulator and kept heat from easily transferring through the glass.

CONS:

• Lost more than 30 degrees Celsius of heat
• The pro-wrap and sleeve did not work as well because they were wet from the 3rd prototype
• The neoprene sleeve is designed to keep things cold, not warm

PROGRESSION:

• Make sure that all materials are dry so that they can be used to their best potential
• Substitute or do not use the neoprene sleeve

Prototype #5

 Material Thermal Conductivity Quantity Cost Plastic bottle 0.02 1 \$0.75 Foam (pro-wrap) 0.02 1 metre \$0.30 Balloon 0.13 1 \$0.25 Plastic poncho 0.2 1 \$0.50 Large Styrofoam cup 0.03 1 \$0.85 Water 0.6 3 ml \$0.75

Total cost: \$3.40

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 99 degrees C 70 Degrees C 29 degrees C

QUALITATIVE RESULTS

• Some open areas on the side of jar (Styrofoam)

PROS:

• The heat was well insulated because of the plastic bottle
• Lost a smaller amount of heat in 15 minutes than the other prototypes

CONS:

• We used water to heat the bottom of our thermos, but the water did not fit within our budget
• Styrofoam was broken up and placed around the outside of the bottle unevenly leaving areas for heat to escape.

PROGRESSION:

• Find a better way to put Styrofoam around bottle without leaving many open areas for heat and energy to escape
• Be within the budget

Prototype #6

 Material Thermal Conductivity Quantity Cost 473 ml plastic bottle 0.02 1 \$0.75 Foam (Pro-Wrap) 0.02 50 cm \$0.15 Large Rubber stopper 0.09 1 \$0.30 Foam Underlay 0.03 10-inch x 5 inch \$0.50 Large Styrofoam cup 0.03 1 \$0.85 Bubble wrap 0.0016 10- inch x 5 inch \$0.90

Total cost: \$3.40

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 92 degrees C 59 degrees C 33 degrees C

QUALITATIVE RESULTS

• Plastic bottle was warm, the bottom was not fully covered with material, so it was hot

PROS:

• The rubber stopper was a good insulator and vacuum seal, so we lost less heat at the top of the bottle.

CONS:

• We lost more than 25 degrees in the final temperature
• Over budget
• no design
• lost a lot of heat at the bottom of the bottle
• the Styrofoam cup did not do much for our prototype
• the bubble wrap with the foam underlay seemed like they did not work well because the bottle was hot by the end of the test

PROGRESSION:

• change the Styrofoam cup or add material to the bottom of the bottle
• be in budget

Prototype #7

 Material Thermal Conductivity Quantity Cost Spherical Styrofoam ball 0.03 5.5-inch Styrofoam ball \$4.00 Aluminum foil 250 4 x 8 sheet \$0.38 Glass jar with lid 1.0 1 \$0.80

Total cost: \$5.18

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 94 degrees C 58 degrees C 36 Degrees C

QUALITATIVE RESULTS

PROS:

• The Styrofoam ball was a thick insulator which absorbed a lot of the heat.
• The jar was smaller, so there was less cold surface area for the heat to escape from.
• Less money was spent on aluminum because it did not take as much as previous prototypes to cover the whole glass jar.

CONS:

• Aluminum and glass were both very hot meaning lots of heat transferred/escaped through the glass and foil.
• The sphere had a gap where both halves conjoined, so to solve the problem we taped the two halves together however heat could’ve easily escaped through the tape as there was no Styrofoam protection
• The bottom and lid of the jar were not wrapped in aluminum foil, so heat could escape more easily from those places.
• Styrofoam was out of the budget.

PROGRESSION:

• Replace the Styrofoam ball with a glass jar as it is cheaper. Encase the smaller glass jar with a bigger glass jar and fill the space in between with foam to recreate the effects of prototype 7 but for cheaper.
• Wrap the entire small jar in aluminum foil including the bottom of the jar.

Prototype #8

 Material Thermal Conductivity Quantity Cost Glass jar with lid 1.0 2 \$1.60 Spray foam 0.03 \$2.00

Total cost: \$3.60

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 93 degrees C * COULD NOT BE RECORDED * N/A

QUALITATIVE RESULTS

• The foam expanded and when the condensation from the inner hot glass jar mixed with the expanding foam it created a vacuum seal that could not be opened therefore, we could not record the results. Pro’s Con’s and progressions could not be recorded; however, we are going to try and recreate the same idea in our next prototype with foam underlay instead.

Prototype #9

 Material Thermal Conductivity Quantity Cost Glass jar with lid 1.0 2 \$1.6 Aluminum Foil 250 4 x 8” piece (x2) \$0.76 Foam Underlay 0.03 4 x 8” piece \$0.38

Total cost: \$2.74

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 95 degrees C 56 degrees C 39 degrees C

QUALITATIVE RESULTS

• jar was warm
• no design
• no water leaked

PROS:

• The aluminum acted as a good reflective layer preventing radiant heat loss.
• The foam acted as a strong insulator preventing conductive heat loss.
• The second glass jar helped prevent heat that passed through all other materials from escaping and created a vacuum seal.
• The entire jar was wrapped in aluminum foil including the bottom and the inner top of the lid.

CONS:

• After doing some research, our group discovered that the shiny side of the aluminum foil needs to be facing inwards to reflect the thermal heat back into the jar. We were not aware of this before and were not paying close attention to which side of the aluminum was facing inwards on previous prototypes.
• The reflective side of the aluminum foil was facing outwards
• Second glass jar was warm which means it did not insulate very well.

PROGRESSION:

• Paint the thermos to make it visually appealing
• Be sure that the reflective side of the aluminum is acing inwards towards the jar.

FINAL PROTOTYPE

 Materials Thermal Conductivity Quantity Cost Glass jar with lid 1.0 2 \$1.6 Aluminum Foil 250 4 x 8” piece (x2) \$0.76 Foam Underlay 0.03 4 x 8” piece \$0.38 Paint 0.2 1 coat \$0.25

Total cost: \$2.99

QUANTITATIVE RESULTS

 Initial Temperature Final temperature Total amount of heat lost 82 degrees Celsius 52 degrees Celsius 30 degrees Celsius

QUALITATIVE RESULTS

• Jar was not hot

PROS:

• Our design was appealing to the eye and had a target audience (the youth of today who love hydro flasks).
• The thermos lost 30 degrees Celsius in 60 minutes while adhering to the \$3.00 budget