Engineering, 23.06.2021 22:50, melwamb

Air at 20oC is used to cool a 20 cm × 20 cm circuit board. 4 cm long aluminium (=230 W. m-1.ºC -1) fins are attached to one side of the board. Each fin has a 2 mm × 2 mm square cross section. The upper surface of the board should be maintained at 80oC. Find the required number of fins to achieve the required cooling. Assume the overall effectiveness is 3 and the convective heat transfer coefficient is 20 W. m-2.ºC -1.

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Air at 20oC is used to cool a 20 cm × 20 cm circuit board. 4 cm long aluminium (=230 W. m-1.ºC -1) f...