Day 5: [TROUBLESHOOTING AND RE-TESTING]

After the thermos was rebuild our initial focus was on troubleshooting. Once the testing took place again for the second time, now with the requirements, it occurred to us that the thermos wasn't retaining all the heat as the bottle still felt warm. There was only a certain spot that was maintaining the heat which was the bottom of the bottle, that held rice. The reason for this is because in current thermoses they hold a rubber support at the bottom which prevents the flask from touching the outer layer. When the flask isn't touching the outer layer, heat isn't being transferred because of the insulation (rubber) between them. In this case, the thick layer of rice at the bottom of our thermos acted as a good heat insulator based on our experience.

Therefore we applied the same method by adding bubble wrap which is a thicker layer of insulation inside of the 2L bottle to surround the plastic bottle, and furthermore having tin foil and tape entwine outside of the 2L bottle to insure extra insulation. We decided to keep the plastic lid of the bottle as it is, because from our research we found out that plastic is a good head insulator and it's a easy material to cut though so we can insert our thermos in. The very last detail we added was a piece of clay for the lid to prevent the heat coming out of the hole that was made for the thermos. The clay would just be placed on top without being glued or taped on so that it can be removed when liquid is needed to be poured in the thermos. Clay is also a good heat insulator because the minerals that it's made out of are low in thermal conductivity. 

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