【摘要】 在液体火箭发动机模态参数辨识领域,频域法仍是模态分析的主流方法。但是该方法存在若干不足,如功率泄露、频率混叠、离线分析等,而且需增加复杂的激振设备。本文将基于时域识别的ARMA时序分析法应用到该领域,计算获得了较为精确的模态参数,并且还进行了液体火箭发动机结构非线性影响检测。该方法提高了计算效率,拓展了液体火箭发动机的参数辨识范围,为发动机在工作环境下的结构参数辨识奠定了基础。更多还原

【Abstract】 In the field of the modal parameters identification of liquid rocket engines,the frequency method is widely used,but it has some shortcomings,such as power reveal,frequency domain aliasing and off-line analysis.Moreover,it may need complex equipment for vibration.In this paper,the method of ARMA based on time-domain identification is applied to this field.By using this method,more accurate modal parameters were obtained by calculation.Besides,the nonlinear effects on the structure of the liquid rocket engine were tested.The method of ARMA improved the computational efficiency and extended the identification range of parameters of liquid rocket engine. It laid the foundation for the parameters identification of the rocket engine in the working condition.更多还原