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>An experimental study of effects of thermophysical properties of thermostatic expansion valve sensor bulb on stability of refrigeration system.
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An experimental study of effects of thermophysical properties of thermostatic expansion valve sensor bulb on stability of refrigeration system.
The combination of increased power dissipation and increased packaging density has led to substantial increases in chip and module heat flux in high-end computers. The challenge has been to limit the rise in chip temperature. In the past virtually all-commercial computers were designed to operate at temperatures above the ambient. However researchers have identified the advantages of operating electronics at low temperatures. The primary purpose of low temperature cooling using vapor compression system are faster switching times of semiconductor devices, increased circuit speed due to lower electrical resistance of interconnecting materials, and a reduction in thermally induced failures of devices and components. Achievable performance improvements range from 1 to 3% for every 10°C lower transistor temperature, depending on the doping characteristics of the chip. The current research focuses on IBM's mainframe, which uses a conventional refrigeration system to maintain chip temperatures below that of comparable air-cooled systems, but well above cryogenic temperatures.; A mathematical model is developed to determine the time constant for expansion valve sensor bulb. (Abstract shortened by UMI.)
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