A refrigerator door of area 0.6 sq.m consists of 25 mm of insulation on top of a thin metal sheet. The film heat transfer coefficients inside and outside the refrigerator are 10.0 and 15.0 W m-2 K-1, respectively, and the thermal conductivity of the insulation is 0.25 W m-1 K-1. If the working temperature of the refrigerator is 0oC and ambient temperature is 20oC, determine the heat flow through the refrigerator door and the temperature of the inside surface of the door.

A refrigerator door of area 0.6 sq.m consists of 25 mm of insulation on top of a thin metal sheet. The film heat transfer coefficients inside and outside the refrigerator are 10.0 and 15.0 W m-2 K-1, respectively, and the thermal conductivity of the insulation is 0.25 W m-1 K-1. If the working temperature of the refrigerator is 0oC and ambient temperature is 20oC, determine the heat flow through the refrigerator door and the temperature of the inside surface of the door.

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.37P

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A refrigerator door of area 0.6 sq.m consists of 25 mm of insulation on top of a thin metal sheet. The film heat transfer coefficients inside and outside the refrigerator are 10.0 and 15.0 W m-2K -1 , respectively, and the thermal conductivity of the insulation is 0.25 W m-1K -1 . If the working temperature of the refrigerator is 0oC and ambient temperature is 20oC, determine the heat flow through the refrigerator door and the temperature of the inside surface of the door.
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