金属热防护系统设计的有限元分析

对可重复使用运载飞行器金属热防护系统进行了有限元分析,计算发现超耐热合金防热结构中下层蜂窝夹芯板的存在会增加结构的质量,但是并不会提高绝热性能,因此改进型防热系统取代了超耐热合金防热系统。比较分析了板间缝隙宽度和辐射率对防热结构底部最大温度的影响,表明减小板间缝隙是消除缝隙辐射的最好办法。分析了模拟条件对热防护系统尺寸设计的影响:初始温度为0℃时比为40℃时最大可以减少17%的厚度和7.7%的质量;考虑热损失厚度最小可以降低26%,质量最小可以降低7%。

Finite Element Analysis of Metallic Thermal Protection Systems Design

The finite element analysis of the metallic Thermal Protection Systems (TPS) for Reusable Launch Vehicles is completed, and it is found that the existing of lower honeycomb sandwich of superalloy metallic TPS concept will increase the TPS mass, but will not improve the insulation ability. So with the development of metallic TPS, the superalloy honeycomb metallic TPS concept is replaced by the improved metallic TPS concept. How much the different gap widths and emittances influence the maximum structure temperature is analyzed and compared, and it is found that the best solution for effectively limiting gap radiation is to design TPS concepts to eliminate the panel-to-panel gap. The effects of several modeling issues on TPS sizing are analyzed, and a change in initial temperature from 40℃ to 0℃ produces the decreases of 7.7% in TPS mass and 17% in thickness. Considering structure heat loss results in the decrease of 7% in TPS mass and 26% in thickness.