The human body can lose heat via conduction and radiation (the other two mechanisms include convection and
Question:
The human body can lose heat via conduction and radiation (the other two mechanisms include convection and latent heat loss through evaporation). Suppose an unclothed human body has a surface area of 1.35 m 2 , an average skin temperature of 32 ºC and an ambient temperature is 15 ºC (the surrounding surfaces also have the same temperature). simplification: assume the relevant latent heat to be 2,400 kJ/kg you can treat this as the T_cold when calculating Carnot efficiency
a. what is the power of net radiation heat loss (in watts) if we assume the human body as a blackbody (a reasonably good assumption).
b. what is the power of net conductive heat loss (in watts) if the thermal conductivity htc for still air is 0.023 W/m/K and the thickness of the boundary layer (near skin) over which the temperature changes linearly is 2 cm
Fundamentals Of Momentum Heat And Mass Transfer
ISBN: 9781118947463
6th Edition
Authors: James Welty, Gregory L. Rorrer, David G. Foster