为了提高空间相机热分析计算的准确度,提出了一种基于中心复合设计的热计算参数修正方法。介绍了中心复合设计方法,对空间相机次镜及遮光罩加热区对次镜的加热效果进行了试验,并根据试验建立了有限元模型。利用中心复合设计法设计了热计算参数,将设计的参数作为不同的工况代入到有限元模型中进行计算,根据计算结果拟合出次镜最高温度、自然对流换热系数和接触传热系数的回归方程,并根据试验结果通过求解回归方程得到最终的热计算参数。最后,将求解后的参数代入到有限元模型中重新进行计算。结果表明,参数修正后的结果与试验结果一致性较好,计算和试验的相对误差为2%,该方法同样适用于其它相机的热计算参数修正。
A method to correct thermal calculation parameters based on the Center Composite Design (CCD)was presented for enhancing the thermal analysis accuracy of a space camera.Firstly,the CCD was introduced,and the thermal tests of second mirror and baffle for the space camera were summarized.The finite element mode of the thermal tests was established and the thermal analysis was dealt with by a software code TMG at different load cases.The parameters of thermal analysis were designed by means of the CCD,then they were taken as the different load cases for the thermal analysis.The regression equations about the highest temperature of second mirror,free convection coefficient and the contact coefficient of heat transfer were fitted according to the results of thermal analysis.The final thermal calculation parameters were obtained by solving the regression equations based on the test results.Finally,the thermal analysis was dealt with again by the parameters that had been solved.The results show that the calculation results of parameters corrected are in agreement with the results of thermal test well,and the relative error is 2%.Moreover,the method can be applied to the thermal analysis of other space cameras and shows a good universality.