How long will Dry Ice last in a Thermos?

In this short video i measure the weight loss of a dry-ice filled thermos to determine the sublimation rate, and the rate of heat-leakage into the thermos, assuming the energy of sublimation is 734 kJ/kg.

A 47 oz thermos lost 12 grams/hour of dry ice, and when placed in a foam box, it lost about 11 grams/hour, which works out to 2.45W and 2.24W of heat transfer respectively. That's actually pretty impressive when you consider that's at a temperature difference of over 100C.

Music:
Kevin Macleod - Lobby Time

Видео How long will Dry Ice last in a Thermos? канала Hyperspace Pirate