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

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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Concept explainers

Energy transfer

The flow of energy from one region to another region is referred to as energy transfer. Since energy is quantitative; it must be transferred to a body or a material to work or to heat the system.

Molar Specific Heat

Heat capacity is the amount of heat energy absorbed or released by a chemical substance per the change in temperature of that substance. The change in heat is also called enthalpy. The SI unit of heat capacity is Joules per Kelvin, which is (J K-1)

Thermal Properties of Matter

Thermal energy is described as one of the form of heat energy which flows from one body of higher temperature to the other with the lower temperature when these two bodies are placed in contact to each other. Heat is described as the form of energy which is transferred between the two systems or in between the systems and their surrounding by the virtue of difference in temperature. Calorimetry is that branch of science which helps in measuring the changes which are taking place in the heat energy of a given body.

Question

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, Ti = 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

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