微通道轴向导热的拉曼测温实验研究及数值模拟

Experimental Study of the Raman Temperature Measurement of the Axial Heat Conduction Inside a Micro-channel and Its Numerical Simulation

建立了使用共焦显微拉曼光谱图的微尺度水温测量方法,并用于单相水的对流传热实验。将实验与数值模拟相结合,研究了微通道内轴向导热对流体的传热影响。研究发现,通道入口处壁面热通量最大、液温和壁温均呈非线性发展;局部Nu数曲线出现奇异点,且奇异点位置随着雷诺数的增大往出口处移动;努塞尔数随着雷诺数的增大而增大。

Proposed was a method for micro-scale measuring water temperature based on the confocal microscopic Raman spectrum and used was the method in question in the convection heat transfer test of single-phase water. In combination of the test with the numerical simulation,the authors studied the influence of the heat conduction in the axial direction inside a micro-channel on the heat transfer of the fluid. It has been found that the heat flux on the wall surfaces at the inlet of the micro-channel is maximal and the liquid and wall temperature all assume a nonlinear development. A singular point will locally appear on Nu number curves and its location will shift to the outlet with an increase of the Reynolds number. In addition,the Nusselt number will increase with an increase of the Reynolds num-ber.