推进剂粘弹性对固体火箭飞行模态特性的影响  

Effect of solid propellant viscoelasticity on flight modalcharacteristics of solid rockets

作　　者：夏鹏 侯凯宇 史晓鸣 高阳 孙晓娇 刘维丽[4] 康海峰 XIA Peng;HOU Kaiyu;SHI Xiaoming;GAO Yang;SUN Xiaojiao;LIU Weili;KANG Haifeng(Shanghai Electro-Mechanical Engineering Institute,Shanghai 201109,China;Shanghai Academy of Spaceflight Technology,Shanghai 201109,China;Shanghai Space Propulsion Technology Research Institute,Shanghai 201109,China;Shanghai Spaceflight Precision Machinery Institute,Shanghai 201600,China)

机构地区：[1]上海机电工程研究所,上海201109 [2]上海航天技术研究院,上海201109 [3]上海航天动力技术研究所,上海201109 [4]上海航天精密机械研究所,上海201600

出　　处：《固体火箭技术》2022年第4期639-647,共9页Journal of Solid Rocket Technology

摘　　要：常规固体火箭振动模态特性分析中不考虑推进剂粘弹性的影响,实际上在飞行过程中推进剂的粘弹性会使固体火箭呈现复杂、变化的模态特性。飞行过程中,一旦结构的某阶模态与燃烧室声腔发生耦合振动,就有可能诱发燃烧不稳定,因此有必要掌握全箭实时模态参数。针对粘弹性推进剂使得火箭飞行过程实时模态参数难以预测的问题,提出了一种数值仿真模型修正方法,以空、满载固体火箭地面模态试验结果与仿真结果进行对比,证明了方法的准确性。对空、满载火箭模态参数进行对比还可以发现,当推进剂厚度随着燃烧逐渐变薄,全箭在弯曲振动中,发动机壳体的截面变形逐渐增大;发动机呼吸振动幅值也随之变大。在已知燃面退移量的前提下,可准确预示全箭在飞行过程中的实时模态参数,极大提升了固体火箭在飞行过程中的振动问题的分析及排查能力。The viscoelasticity influence of propellant is not considered in the conventional analysis of vibration characteristics of solid rockets.In fact,the viscoelastic properties of the propellant will lead to the complex and variable modal characteristics of solid rockets during flight.During the flight,once a certain order mode of the structure and the acoustic cavity of the combustion chamber are coupled to vibrate,it may induce combustion instability,so it is necessary to master the real-time modal characteristics of the whole rocket.In view of the problem that viscoelastic propellant makes it difficult to predict real-time modal parameters during rocket flight,a numerical simulation and model correction method was proposed.The modal frequency error between the unloaded and full-loaded solid rocket ground modal test results and the simulation results indicates the method has high accuracy.Comparing the modal parameters of unloaded and full-loaded rocket,it can also be found that during the combustion,the thickness of the propellant becomes thinner,the overall stiffness of the propellant continues to decrease and the motor cross-section deformation gradually increases when bending vibration occurs;the overall viscoelastic damping effect of the propellant continues to weaken,and the amplitude of motor breathing vibration also becomes bigger.Under the premise of known combustion surface regression,the modal characteristics of the entire rocket at any time can be accurately predicted,which greatly improves the analysis and troubleshooting capabilities of vibration problems during the solid rocket's working process.

关 键 词：粘弹性 固体推进剂 模态应变能法 固体火箭 模态分析 

分 类 号：V414[航空宇航科学与技术—航空宇航推进理论与工程]