塞块式量热计长时间变工况热流测量

Investigation of Slug Calorimeter for Measuring Multi Invariable Heat Flux Environment

采用塞块式量热计对200 MW燃气流风洞试验件表面热流进行测量,试验过程中塞块式量热计遍历风洞的启动、模型变攻角、停车等阶段。为准确获取不同攻角条件下模型表面热流值,采用数值仿真对塞块式量热计的传热特性进行分析,研究背温反算的热流值与输入热流边界条件的差异,提出塞块式量热计长时间使用的修正方法,该修正方法通过一次稳态热流源的标定即可获得其他热流边界条件下的结果,从而简化标定过程。将修正方法应用于长时间变工况热流测量修正时,偏差小于2%,增加了塞块式量热计的使用范围,通过一次风洞试验,获取多个稳态工况条件下试验件表面热流值,节约风洞运行成本。此外,该修正方法也可用于高热流瞬时测量结果的修正。

Slug calorimeters are used for characterization of thermal environment at 200 MW combustion gas wind tunnel.The test article inserted with slug calorimeter experiences multi invariable heat flux environment during the test.In order to analyze the difference between the heat flux calculated from the back-face temperature and the incident heat flux,Finite Element Analysis(FEA)models are created using the commercial software,where conduction heat losses and the variable heat flux boundary condition are simulated.The heat flux calculated will be nearly same in conditions of equal back-face temperature and heat flux boundary condition.The conclusion is confirmed by the experiments.