LED灯表面对流换热系数的测算研究

Research on The Surface Convection Heat Transfer Coefficient of LED Lamp

提出了一种在第三类边界条件下,根据LED灯瞬态温度场的变化规律,通过对其表面温度的实际数值测定来推算LED灯表面对流换热系数的快速测定方法。基于对流热平衡理论,设计了一种可以在较高表面换热强度条件下进行测试的装置,通过实验测定LED灯上下表面的温度,结合曲线拟合对实测数据进行数理分析,得到较宽范围内的表面对流换热系数。实验结果表明:该测试方法简单、实用,测试时间较短(实验准备与数据测定大约需要30 min),测试精度较高(数据拟合误差不高于0.2%),可靠性强,可以用于工程热设计等多种相关发热体表面对流换热系数的测定。

This paper presented a rapid determination method, which was based on the variation of LED lamp transient temperature field and the third boundary condition. It used the surface temperature measured values of LED lamp to calculate its surface convective thermal transfer coefficient. Based on balance theory of convective heal, we designed test equipment that can work under a higher intensity of thermal transfer conditions of the surface. Experimental results show that the test method is simple and practical, the time is short （ -30 min）, and the accuracy is high （ 〈0.2% ） and reliable. It can be used for projects that related to surface thermal convection coefficient measurements.