红外热波成像法测量薄板局部换热系数

Measuring local heat transfer coefficient by infrared thermal wave imaging

通过连续激光调制对薄板试样进行局部周期加热，采用红外扫描测温技术记录动态温度分布。利用博里叶变换分析温度基波相位和幅值变化，进而推算壁面的局部换热系数。介绍了该方法的测量原理，在风洞中对两种不同厚度的薄板进行了实验研究，并对实验结果进行了分析和讨论。

When a thin plate is heated by a beam of modulated continuous laser, a temperature wave generates and propagates along the plate with amplitude decay and phase delay. The amplitude and phase distribution depend on material thermal properties, wall thickness and local heat transfer coefficient. The measurement theory of this method is introduced and analyzed. A experimental set-up is established to study heat transfer of thin plate in wind tunnel. Dynamic temperature distribution is recorded by infrared scanning technology. Local heat transfer coefficient is calculated by analyzing phase and amplitude distribution of basic harmonis through Former analysis. Two thin plates with different thickness are studied. Experimental results are discussed and compared with known correlation.