An average man has a body surface area of 1.8 m2 and a skin temperature of 330C. The convective heat transfer coefficient for a clothed person walking in still air is expressed as h= 8.6V0.53 where V is the walking velocity in m/s. Assuming the average surface temperature of the clothed person to be 300C, determine the rate of heat lost by convection from an average man walking in still air at 100C at a walking velocity of 1.2 m/s.

An average man has a body surface area of 1.8 m2 and a skin temperature of 330C. The convective heat transfer coefficient for a clothed person walking in still air is expressed as h= 8.6V0.53 where V is the walking velocity in m/s. Assuming the average surface temperature of the clothed person to be 300C, determine the rate of heat lost by convection from an average man walking in still air at 100C at a walking velocity of 1.2 m/s.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.22P

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An average man has abody surface area of 1.8m2 and a skin temperature of 33degrees celcius .The convection heat transfer coefficient for a clothed person walking in still air is expressed as {h,8.6V^0.53}FOR 0.5<v<2m/s,where V is the walking velocityin m/s.Assuming the average surface temperature of the clothed person to be 30degrees celcius, determine the rate of heat loss from an average man walking in still air at 10degrees celcius by convectionat a walking velocity of (a)0.5m/s (b)1.0m/s (c)1.5m/s (d)2.0m/s
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