An electronic component with dimension of 5 cm wide, 6 cm high, and 9 cm long is cooled by aluminum heat sink (9 cm × 5 cm wide and emissivity of 0.9) to its top surface as shown in Figure 2. The aluminum heat sink was designed with seven fins, which are 6 mm high, 3 mm thick, and 9 cm long. A fan blows air at 30 °C parallel to the passages between the fins. The heat sink is to dissipate 10 W of heat. The fins and the base plate to be nearly isothermal. Suggest the minimum free-stream velocity the fan needs to supply if the base temperature of the heat sink is not to exceed 50 °C to avoid overheating. Please consider your analysis for both laminar and turbulent flow conditions.

An electronic component with dimension of 5 cm wide, 6 cm high, and 9 cm long is cooled by aluminum heat sink (9 cm × 5 cm wide and emissivity of 0.9) to its top surface as shown in Figure 2. The aluminum heat sink was designed with seven fins, which are 6 mm high, 3 mm thick, and 9 cm long. A fan blows air at 30 °C parallel to the passages between the fins. The heat sink is to dissipate 10 W of heat. The fins and the base plate to be nearly isothermal. Suggest the minimum free-stream velocity the fan needs to supply if the base temperature of the heat sink is not to exceed 50 °C to avoid overheating. Please consider your analysis for both laminar and turbulent flow conditions.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

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