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Engineering, 09.07.2021 19:20 help4068

Adding fins to a surface can increase the surface area but may also serve to decrease the convective heat transfer coefficient by decreasing the velocity of the fluid. If an array of aluminum fins that are 50 mm long, 0.5 mm thick, and equally spaced 4mm apart (S=4mm) are added to a plane wall, determine the change in heat transfer if the convection coefficient associated with the bare wall is 40 W/m^2K is reduced to 30 W/m^2K when the fins are added. Report your results as a percentage change in heat transfer (q_withfins-q_withoutfins)/q_withou tfins. a. The percentage increase in heat transfer is approximately 1300%
b. The percentage increase in heat transfer is approximately 600%
c. The percentage increase in heat transfer is approximately 200%
d. The percentage decrease in heat transfer is approximately 600%

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