A student is standing inside a large classroom with temperature controlled at 20°C. For a heat transfer purposes, the student can be modeled as a 30-cm diameter, 170-cm long vertical cylinder with both the top and bottom surfaces insulated. The side surface of the student is at an average temperature of 34°C. With a convection heat transfer coefficient of 15 W/m².°C, determine the rate of heat loss from this student by convection to the room. How about the radiation loss if the emissivity of the human skin is taken as 0.96? Could the radiation heat loss be neglected compared to convection heat loss?

A student is standing inside a large classroom with temperature controlled at 20°C. For a heat transfer purposes, the student can be modeled as a 30-cm diameter, 170-cm long vertical cylinder with both the top and bottom surfaces insulated. The side surface of the student is at an average temperature of 34°C. With a convection heat transfer coefficient of 15 W/m².°C, determine the rate of heat loss from this student by convection to the room. How about the radiation loss if the emissivity of the human skin is taken as 0.96? Could the radiation heat loss be neglected compared to convection heat loss?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Question

B. A student is standing inside a large classroom with temperature controlled at 20°C. For a
heat transfer purposes, the student can be modeled as a 30-cm diameter, 170-cm long
vertical cylinder with both the top and bottom surfaces insulated. The side surface of the
student is at an average temperature of 34°C. With a convection heat transfer coefficient
of 15 W/m².°C, determine the rate of heat loss from this student by convection to the
room. How about the radiation loss if the emissivity of the human skin is taken as 0.96?
Could the radiation heat loss be neglected compared to convection heat loss?

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