两种电子器件用重力型热管散热器的换热特性

鉴于重力型热管特有的优良特性，设计开发了两种结构形式不同的重力型热管散热器，以用于电子器件冷却.其冷凝段分别采用单根粗的或7根较细的热虹吸管，蒸发段都采用同样的平板容积型蒸发器.为了对散热器的传热性能进行研究，建立了风洞测试系统.实验用电加热模拟发热电子器件，在风洞中对不同加热功率和风速下散热器的性能进行了测试.从总热阻和当量对流换热系数两方面比较了两种散热器的散热能力.研究表明：两种散热器都具有良好的传热性能，在散热功率小于78.47 W时能够满足电子器件的冷却要求;采用7根较细热虹吸管的散热器比采用单根粗热虹吸管的散热器性能好，原因是7根较细的热虹吸管可以将热量分散开来，提高了翅片热效率.

Heat transfer characteristics of two different thermosyphon radiators for electronic device

Thermosyphon cooling is a promising cooling technique for electronic device with increasing heat generation, in which heat is transferred from evaporator to condenser with a relatively small temperature difference. Two types of thermosyphon radiators with different structures on condensation sections were developed. One thicker or seven thinner thermosyphon pipes were used respectively in the condensation sections, and flat plate volume evaporators were used in both types. A testing system for the characteristics of radiators was established. Based on the method of simulating electronic device with a heated copper block, the surface temperature of the copper block at different heating powers and different wind speeds was tested in the wind tunnel, and a comparison of total thermal resistance and equivalent convection heat transfer coefficient for radiators was made. The result showed that the two radiators could both meet a cooling demand below 78.47 W. The radiator with seven thinner thermosyphon pipes had stronger heat transfer capability, because heat was dispersed by all of the seven thermosyphon pipes, which enhanced the heat transfer efficiency of heat sink.