PROBLEM 1 Consider an adult human standing in the centre of a closed room. The air and room’s walls, ceiling and floor surrounding the being are at a temperature of 25oC. Assume for the adult body a temperature of 37oC, a surface area of 1.7m2, an emissivity of 0.95 and the heat transfer coefficient of 6 W/m2K for natural convection between the air and the body. Question: (a) Describe the modes of heat transfer between the adult human and their surroundings. What are some assumptions that must be made before calculating the heat transfer rates? (b) Determine the total rate of heat transfer from the adult into their surroundings.

PROBLEM 1 Consider an adult human standing in the centre of a closed room. The air and room’s walls, ceiling and floor surrounding the being are at a temperature of 25oC. Assume for the adult body a temperature of 37oC, a surface area of 1.7m2, an emissivity of 0.95 and the heat transfer coefficient of 6 W/m2K for natural convection between the air and the body. Question: (a) Describe the modes of heat transfer between the adult human and their surroundings. What are some assumptions that must be made before calculating the heat transfer rates? (b) Determine the total rate of heat transfer from the adult into their surroundings.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.13P

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