A person wearing a heavy parka is standing in a cold wind. Describe the modes of heat transfer determining heat loss from the person’s body.
GIVEN
- Person standing in a cold wind, wearing a heavy parka
FIND
(a) The modes of heat transfer
SKETCH
The thermal circuit for the situation is shown above. Assume that the person is wearing one other
garment, i.e., a shirt, under the parka. The modes of heat transfer include conduction through the shirt
and the parka and convection from the outer surface of the parka to the cold wind. We expect that the
largest thermal resistance will be the parka insulation. We have neglected radiation from the parka
outer surface because its influence on the overall heat transfer will be small compared to the other
terms.
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