基于高温瞬态热响应的石英窗口导热系数反演

Inversion of thermal conductivity of quartz window based on transient thermal response at high temperature

提出一种利用高温加热下瞬态热响应信息来同时反演石英窗口在不同温度下导热系数的方法。结合实验测试过程,首先建立石英窗口-石墨板-石英窗口三明治结构高温非灰体辐射-导热耦合传热模型。再通过实际测试温度响应结果和材料光谱辐射特性参数,构建石英窗口导热系数的遗传算法反演辨识模型。采用1100 K加热条件下实验数据,反演辨识获得了常温至1100 K石英窗口导热系数介于1.35~2.58 W/(m·K),并拟合出高温导热系数关联式。结果表明:该材料辐射对导热系数影响随温度升高而增大,在1100 K下辐射影响占比16.12%。最终通过变工况的高温传热过程测试,验证了方法的可靠性及导热系数数据的准确性。

A method for simultaneous inversion of thermal conductivity of quartz window at different temperatures was presented by using transient thermal response information under high temperature heating.Combining the experimental test process,a high-temperature non-gray body radiative and conductive heat transfer model with a quartz window-graphite plate-quartz window sandwich structure was established firstly.Through the actual temperature response and the material’s spectral radiation characteristic parameters,the genetic algorithm was used for constructing the inversion and identification model of the thermal conductivity of quartz window.The thermal conductivity of quartz window was inversed by the result data of 1100 K heating conditions,ranging from 1.35 to 2.58 W/(m·K)at room temperature to 1100 K,and the relationship between thermal conductivity and temperature was fitted.The influence of radiation on the thermal conductivity of the material increased with the temperature,accounting for 16.12%at 1100 K.Finally,the method and the accuracy of the thermal conductivity data were verified by the additional high-temperature tests.