A heat sink made of an array of fins that have a straight, rectangular cross section is used to cool an electronic micro-chip module, as schematically shown in the figure. The heat sink (base and fins) is made of copper, and each fin is 3 mm thick and 30 mm long. If the fin-base temperature is 85°C and the cooling air is at 25°C with an average convective heat transfer coefficient of h̅_c = 100 W/m² K, determine the temperature distribution in one fin and the rate of heat transferred per unit width of the fin. If the fins are made of aluminum instead, what is the change in the rate of heat dissipated by the aluminum

fin of the same thickness? For the numerical analysis in both the cases, consider a minimum of 11 nodes from the base to tip (i.e., 3 mm apart) and convective heat transfer from the fin tip. Compare the results with the one-dimensional fin analysis of Chapter 2.

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