论文部分内容阅读
微细通道内的可压缩流动换热特性研究是一个新兴的研究领域。利用数值方法讨论了压力功和粘性耗散对微细光滑管内可压缩流动换热特性的影响 ,得出以下结论 :微细管内 Ec沿管长是变化的 ,仅依据入口处的 Ec对压力功及粘性耗散的作用进行取舍是不确切的 ;等热流及等壁温换热条件下的计算结果显示 ,在入口 Ma及长径比较大时 ,考虑压力功及粘性耗散时得出的 N u要小于常规尺度管的理论值 ,在等壁温情况下 ,甚至出现了热流方向发生变化的情况
The study of compressible flow heat transfer in microchannels is an emerging field of research. The effect of pressure work and viscous dissipation on the compressible flow heat transfer in a fine smooth tube was discussed by using numerical method. The following conclusions were obtained: the variation of Ec along the tube length in the capillary tube was only based on the influence of Ec on pressure function and viscosity Dissipation effect is not exact. The calculation results under constant heat flow and isothermal wall heat exchange show that at the entrance of Ma and the large aspect ratio, considering the pressure work and viscosity dissipation, Is smaller than the theoretical value of the conventional scale tube, and even under the condition of equal wall temperature, even the situation that the direction of the heat flow changes