Humans are able to control their heat production rate and heat loss rate to maintain a nearly constant core temperature of Tcore=37°C under a wide range of environmental conditions. This process is called thermoregulation. From the perspective of calculating heat transfer between a human body and its surroundings, we focus on a layer of skin and fat, with its outer surface exposed to the environment and its inner surface at a temperature slightly less than the core temperature, T; = 35° C. Temperature of surrounding air is 10°C. Consider a person with a skin/fat layer of thickness L = 3 mm and effective thermal conductivity k = 0.3 W/m.K and person has a surface area A= 1.8 m?. The person is dressed in a bathing suit with an extremely low thermal conductivity of 0.014 W/m K. The emissivity of the outer surface of wet suits is 0.95. 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 what is the resulting skin temperature? hradiation= 5.9 W/m² K and hair = 2 W/m2 K

Humans are able to control their heat production rate and heat loss rate to maintain a nearly constant core temperature of Tcore=37°C under a wide range of environmental conditions. This process is called thermoregulation. From the perspective of calculating heat transfer between a human body and its surroundings, we focus on a layer of skin and fat, with its outer surface exposed to the environment and its inner surface at a temperature slightly less than the core temperature, T; = 35° C. Temperature of surrounding air is 10°C. Consider a person with a skin/fat layer of thickness L = 3 mm and effective thermal conductivity k = 0.3 W/m.K and person has a surface area A= 1.8 m?. The person is dressed in a bathing suit with an extremely low thermal conductivity of 0.014 W/m K. The emissivity of the outer surface of wet suits is 0.95. 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 what is the resulting skin temperature? hradiation= 5.9 W/m² K and hair = 2 W/m2 K

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter11: Energy In Thermal Processes

Section: Chapter Questions

Problem 40P: The thermal conductivities of human tissues vary greatly. Fat and skin have conductivities of about...

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