液体运载火箭纵向振动结构动力学模型应用研究

摘要

In order to perform the POGO analysis and coupled load analysis, the longitudinal structural models must be derived and the longitudinal structural dynamical characteristics must be calculated during the engineering development of the structural dynamics of the liquid-propellant launch vehicles. The focus on the structural models is how to establish the models for the liquid-propellant tanks. This paper has derived and established the multi-mass simplified models on the basis of the references 4 and 5 to overcome the over-time-consuming defect of the virtual mass method by MSC.Nastran and the poor calculating precision of high frequency of the single-mass models. Results of the example for validation indicate that the calculating precision of high frequency has been improved remarkably and the efficiency of calculation has been enhanced greatly.%在液体运载火箭结构动力学工程研制设计中，为了进行POGO分析和星箭耦合载荷仿真预示，一般需要进行运载火箭纵向结构动力学模型的建立及其纵向动力学特性计算，建模过程中重点关注环节是加注液体推进剂的贮箱的简化建模，为了克服MSC.Nastran虚质量法计算耗时长的劣势和单质量块简化模型高阶频率计算精度较差的缺点，基于文献方法进行了多质量块简化模型的推导和建立，通过算例表明，采用多质量块简化模型在保证计算精度的同时，可以大大提高计算效率。