Integrated circuit (IC) boards are stacked within a duct and dissipate a total of 500 W. The duct has a square cross section with
Your assignment is to develop a model to estimate the outlet temperature of the air,
(a) Assuming a surface temperature of 37°C, estimate the average free convection coefficient,
(b) Assuming a surface temperature of 37°C, estimate the average linearized radiation coefficient,
(c) Perform an energy balance on the duct by considering the dissipation of electrical power in the ICs, the rate of change in the energy of air flowing through the duct, and the rate of heat transfer from the air in the duct to the surroundings. Express the last process in terms of thermal resistances between the mean temperature,
(d) Substitute numerical values into the expression of part (c) and calculate the air outlet temperature,
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Fundamentals of Heat and Mass Transfer
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