Engineering, 16.10.2020 07:01 alfarodougoy8lvt

In order to increase heat transfer between a stainless steel (k = 15 W/m-K) wall and the surrounding air, eight parabolic fins made of aluminum (k = 186 W/m-K) are attached to the surface of the wall. The surrounding air is a temperature of 20°C and the convection coefficient between the wall and the air is found to be h = 200 W/m^2 -K. The wall has a height of 50 mm and a width of 200 mm, while each fin has a base thickness of 4 mm and a length of 10 mm. The surface temperature of the wall is 300°C. Required:
a. Calculate the efficiency of a single fin, ηf
b. Calculate the overall surface efficiency, ηe for the finned surface.

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In order to increase heat transfer between a stainless steel (k = 15 W/m-K) wall and the surrounding...

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