复杂航天器结构火工冲击环境预示方法研究

针对复杂航天器结构在宽频、瞬态火工冲击载荷激励下其响应难以预示的问题，以某型复杂卫星结构为研究对象开展了火工冲击环境预示方法研究。首先，推导了基于加速度频响函数(FRF)的虚拟模态综合法(VMSS)的理论公式。对于复杂卫星结构各子系统动力学特性存在较大差异的特点，建立了有限元-统计能量分析（FE-SEA）混合模型，并进行响应计算，获得了加速度频响包络曲线及模态数曲线，为虚拟模态综合法的响应预示提供输入。然后，对复杂卫星结构推进舱底板和侧板的火工冲击响应进行了计算分析。最后，将计算结果与整星火工分离冲击试验结果对比发现两者基本保持一致。研究结果表明，联合FE-SEA混合建模技术和虚拟模态综合法能够对复杂卫星结构火工冲击环境进行较为精确地预示。

Study on Prediction Methods of Pyroshock Environment for Complex Spacecraft Structures

Aiming at the problem that the response of complex spacecraft structures under the excitation of pyroshock with the characteristics of wide frequency and transient state is difficult to be calculated, the prediction method of pyroshock environment for a complex satellite structure is researched. Firstly, the basic theory of the virtual mode synthesis and simulation (VMSS) based on the acceleration frequency response function (FRF) is deduced. Then, the finite element-statistical energy analysis (FE-SEA) hybrid model of the complex satellite is established and the steady acceleration FRF curves and modal number curves are obtained, providing the initial inputs of calculation with VMSS. Furthermore, the pyroshock responses of the bottom panel and side panel of the propulsion cabin are calculated and analyzed. Finally, the computed results are compared with the ones of the whole satellite separation experiment, and the two results are basically consistent. The analysis indicates that the prediction method combining the FE-SEA hybrid modeling technique and VMSS is reliable for the prediction of pyroshock environment.