【摘要】 设计了一种用来测试微通道换热性能的实验装置。该系统由微通道换热器、模拟热源、微型水泵、连通管、测试三通及其它测试元件构成。通过检测温度、压力和流量等参数能够得到微通道的传热和摩阻参数。针对该实验装置,对微通道中流体的压降和传热分别进行分析和研究。实验表明,当微通道水力直径为381μm时,宏观理论公式已不适用于微通道摩阻及其换热的计算。此时,微通道的摩阻比宏观理论计算值小31.6%～41.9%;微通道结构具有良好的换热性能,其Nu可达9.2。更多还原

【Abstract】 An experimental apparatus is developed for testing the heat-exchange performance of microchannel structures. It consists of microchannel heat exchangers,a simulated heat source,a micro-pump,a few of pipes,some three-way pipes and other test devices. The heat exchange coefficients and the fluid resistant in microchannels can be obtained by testing temperature,pressure and flow rate. The fluid resistance and heat transfer performance of microchannels are analyzed and investigated based on this experimental apparatus. It is shown that classical macroscopic formulas are not applicable for calculating friction resistance and heat exchange coefficients when channel hydraulic diameter is 381 μm. In this case,the flow resistance number is from 31.6% to 41.9% smaller than that of calculated valne,and the structure has a satisfied heat transfer performance with Nussle number being 9.2.更多还原