电子设备的蒸气压缩冷却方法（Vapor Compression Cooling in Electronicsa）.ppt

Vapor Compression Cooling (VCC) in Electronics Outline Benefits Disadvantages History Basic operation Engineering Design Cold plate Refrigerants Capillary tube Condensation Product Reliability Current applications: Supercomputer and Mainframe Cooling Current research: Microscale VCRS Benefits Allows cooling to below ambient temperatures, increasing performance, reliability, and allowing operation in higher temperatures. High COP (around 2 to 3). Ability to remove very large heat loads. Widely available; compressor and fan only moving parts, stable, and reliable. (moran, 2001). Low mass flow rate of refrigerant needed. Ability to transport heat away from its source. COP up to 3 times greater than thermoelectric coolers or more. (peeples, 2001) Benefits Benefits The following physical parameters favor low temperature operation: carrier mobility, and junction leakage. Although at low temperatures there is an increase in the failure rates due to hot carriers, overall failure rates decrease at lower temps due to the overall increased characteristics mentioned previously (Moran,2001). Definitions: Carrier mobility- velocity of charge carriers in a solid material with an electric field applied to it (Wikipedia, /wiki/Electron_mobility). Hot carriers- high energy carriers (Moran,2001). Junction leakage-undesirable conductive paths in certain components, for instance, in capacitors. Also, a pathway through which electric discharge may slowly take place (IEEE Standard Dictionary of Electrical and Electronics Terms). Benefits Much like heat pipes, vapor compression coolers use the high heat of vaporizations of the working liquid to remove large amounts of heat. Therefore, low mass flow rates required. Advantage over a chilled liquid loop that requires a much higher mass flow rate. Much like heat pipes, VCCs use the high heat of vaporization of liquids to transport large amounts of heat, thus low amounts of liquid are required. However, in chilled liquid loop co