Engineering, 12.11.2019 02:31 amorosoavap5cejz

For heat transfer purposes, a human body can be modeled with a layer of skin 3-mm thick which inner temperature (slightly less than the core temperature) of 35o c and thermal conductivity of 0.3 w/m k. to reduce the heat loss rate, a person wears special sporting gear (snow suit and wet suit) made from nanostructured silica aerogel insulation with an extremely low thermal conductivity of 0.014 w/m k. the emissivity of the outer surface of the snow and wet suits is 0.95. assume a person has a surface area of 1.8 m 2 and is dressed in a suit. take the surrounding and air temperature to be both at 10o c with convection coefficient of 2 w/m2 k for air and 200 w/m2 k for water. what thickness of aerogel insulation is needed to reduce the heat loss rate to 100 w (a typical metabolic heat generation rate) in air and water? what are the resulting skin temperatures?

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For heat transfer purposes, a human body can be modeled with a layer of skin 3-mm thick which inner...