This paper reports the results of CFD analysis to cool the 30-W socketed CPU of a desktop computer with minimum air flow rate and minimum heat sink size. This was achieved using only the fan in the power supply for all air movement in the chassis. A duct was employed to direct the air flow over the CPU and then to the inlet air vents of the power supply. Use of this duct allowed more than 10°C reduction of the CPU case temperature, relative to an unducted design. The CFD analysis results were confirmed by experiment, and the predicted CPU case temperatures agreed within ±2.9°C of the experimental values for the ducted cases. This paper describes the methodology of CFD analysis for the heat sink/duct design, and describes experimental procedures to validate the predictions.

Issue Section:
Technical Papers
Keywords:
microcomputers, cooling, computational fluid dynamics, pipe flow, heat sinks
Topics:
Air flow, Computational fluid dynamics, Computers, Design, Heat sinks, Temperature, Ducts, Vents, Modeling, Computer simulation
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