A 15 cm x 20 cm hot surface at 85°C is to be cooled by attaching 4 cm long aluminum (k = 237 W/m-°C) fins of 2 mm x 2 mm square cross section. The temperature of surrounding medium is 25°C and the heat transfer coefficient on the surfaces can be taken to be 20 W/m²-°C. If it is desired to triple the rate of heat transfer from the bare hot surface, determine the number of fins that needs to be attached. plot the number of fins as a function of the increase in the heat loss by fins relative to no fin case (i.e., overall effectiveness of the fins) in the range of 1.5 to 5. Discuss the results.

A 15 cm x 20 cm hot surface at 85°C is to be cooled by attaching 4 cm long aluminum (k = 237 W/m-°C) fins of 2 mm x 2 mm square cross section. The temperature of surrounding medium is 25°C and the heat transfer coefficient on the surfaces can be taken to be 20 W/m²-°C. If it is desired to triple the rate of heat transfer from the bare hot surface, determine the number of fins that needs to be attached. plot the number of fins as a function of the increase in the heat loss by fins relative to no fin case (i.e., overall effectiveness of the fins) in the range of 1.5 to 5. Discuss the results.

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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