Prototype Testing Experiment:
Purpose:
The purpose of the testing experiment is to figure out which prototypes loses the least amount of heat over a specific amount of time.
Materials:
– Hot plates
– 500 mL Beaker
– Tongs
– Brick
– Prototypes
– Water
– Timer
– Test probe
Safety:
We used tongs to pour the water into our prototypes so that we did not burn our hands on the hot beakers.
We watched the hot plate at all times while it was on to make sure that nothing caught on fire.
After pouring the boiling water from the beaker into the prototypes, we used the tongs to place the hot beaker onto a brick so that it does not get exposed to an extreme temperature change which would cause the beaker to shatter.
Procedures:
1. Plug in a hot plate and crank it to full heat.
2. Fill glass beaker with 150 mL of water (any temperature).
3. Place the glass beaker on top of the hot plate.
4. Use a test probe to monitor the heat of the water (without touching the bottom of the beaker).
5. When the water has reached 100° C, use tongs to pour the boiling water from the beaker into the prototype.
6. Set a timer for 15 minutes once the water has been poured in and the prototype has been sealed.
7. Place the hot beaker on a brick using tongs.
8. Turn the hot plate off and unplug it.
9. When the timer is done, open the prototype and test the temperature of the water using the test probe.
10. Record temperature of the water after 15 minutes and the temperature change.
Data:
Prototype #3 let the least amount of heat out after 15 minutes.
Prototype #1
Materials, Cost
– Milk carton – $0.50
– 2 Styrofoam Cups – $1.00
– 2 inches of tape – $0.10
– Aluminum foil – $1.00
Total Cost: $2.60
Picture:
Performance:
After 15 minutes the temperature of the water was 73 degrees and the temperature drop was 27 degrees.
Pros:
– Styrofoam was a good insulator and kept a lot of the heat in
Cons:
– Was not sealed well causing a lot of heat loss due to convection
Progression:
We realized that since prototype was not sealable, a lot of the heat was being let out of the cup due to convection. To stop this from happening, we decided to use a bottle or something that we could seal so that the heat stayed in the bottle.
Prototype #2:
Materials, Cost:
– Plastic Bottle (with lid) – $0.60
– 2nd plastic bottle (no lid) – $0.30
– Aluminum foil – $1.50
– Tape – $0.10
Total Cost – $2.50
Picture:
Performance:
After 15 minutes the temperature was 80 degrees and the temperature drop was 20 degrees.
Pros:
– bottle was sealed to minimize heat loss
– second bottle used to minimize heat loss and prevent against convection by keeping the hot air in
Cons:
– holes in the second bottle let heat out (convection)
Progression:
The main problem with this prototype is that the second layer of plastic bottles which was designed to keep heat in had many holes because we only used a little bit of tape to seal it. This caused some heat to leave the bottle due to convection.
Prototype #3
Materials/Cost
Milk carton – $0.50
Glass bottle (with lid) – $0.80
Foam insulator – $1.60
Total cost – $2.90
Picture
(Tape was taken off before the final test and was only used to keep the insulator from over flowing)
Performance:
After 15 minutes the temperature of the water was 88 degrees and the temperature dropped 12 degrees.
After 1 hour the temperature was 71 degrees and the temperature drop was 29 degrees.
Pros:
– glass is a good insulator and kept the water in
– no holes or places where heat could escape due to convection
– sealed with a lid
Cons:
– the lid of the bottle was made with some kind of metal and was not a very good insulator.
Progression:
This prototype performed pretty well as it did not let out much heat. The only area where we could have improved is with a better lid because the metal lid was more of a conductor and heat passed through it due to conduction. We can tell this happened because it became very hot by the end of the test.