Q1 A diagram of a heat sink to be used in an electronic application is shown below. There are a total of 9 aluminium fins (k = 175 W/m K, C = 900 J/kg K, p= 2700kg/ m') of rectangular cross-section, cach 60 mm long, 40 mm wide and 1 mm thick. The spacing between adjacent fins, s, is 3 mm. The temperature of the base of the heat sink has a maximum design value of T, = 60°C, when the external air temperature T, is 20°C. Under these conditions, the extemal heat transfer coefficient h is 12 W/m K. The fin may be assumed to be sufficiently thin so that the heat transfer from the tip can be neglected. The surface temperature T, at a distance, x, from the base of the fin is given by: al

Q1 A diagram of a heat sink to be used in an electronic application is shown below. There are a total of 9 aluminium fins (k = 175 W/m K, C = 900 J/kg K, p= 2700kg/ m') of rectangular cross-section, cach 60 mm long, 40 mm wide and 1 mm thick. The spacing between adjacent fins, s, is 3 mm. The temperature of the base of the heat sink has a maximum design value of T, = 60°C, when the external air temperature T, is 20°C. Under these conditions, the extemal heat transfer coefficient h is 12 W/m K. The fin may be assumed to be sufficiently thin so that the heat transfer from the tip can be neglected. The surface temperature T, at a distance, x, from the base of the fin is given by: al

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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