摘要
固体火箭从发射筒发射过程中,采用弹性支撑降低火箭结构与发射筒内壁接触引起的冲击,弹性支撑力学模型对火箭发射过程中结构振动响应计算存在影响。利用多体动力学建立包含火箭、发射筒、弹性支撑在内的发射动力学模型,在火箭发射物理过程分析基础上,利用ANSYS/LS-DYNA软件建立火箭壳体与弹性支撑局部有限元模型,获得了火箭壳体与弹性支撑接触面积变化对支撑刚度影响规律,在此基础上,提出了用于火箭发射多体动力学建模的弹性支撑改进模型,求解弹性支撑模型改进前后火箭发射过程结构振动响应与弹性支撑支反力,分析了弹性支撑模型改进对结构振动响应的影响及其原因。结果表明:提出的弹性支撑改进模型可以准确描述火箭尾部结构脱离弹性支撑过程中接触面积逐渐变化到零的物理过程;与弹性支撑模型改进前相比,改进后结构弯矩响应峰值显著减小。该成果有助于准确评估火箭发射过程结构响应水平,对于火箭结构精细化设计具有工程意义。
In process of solid rocket launching from launcher,elastic support is used to reduce impact caused by contact between rocket structure and inner wall of launcher.The mechanical model of elastic support affects calculation of structural vibration response in process of rocket launch.The launch dynamic model including rocket,launcher and elastic support was established using the theory of multi-body dynamics.Here,based on physical process analysis of rocket launch,the local finite element model of rocket shell and elastic support was established by using the software ANSYS/LS-DYNA,and influence laws of change of contact area between rocket shell and elastic support on support stiffness was obtained.An improved elastic support model was proposed for multi-body dynamic modeling of rocket launch.The structural vibration responses and elastic support reaction forces in rocket launch process before and after improvement of elastic support model were solved.Effects of improvement of elastic support model on structural vibration response and its causes were analyzed.The results showed that the improved elastic support model can accurately describe the physical process of contact area gradually changing to zero during rocket tail structure separating from elastic support;compared with the elastic support model before being improved,the peak moment response of the structure after being improved is significantly reduced;the study results are helpful to accurately evaluate the structural response level in rocket launch process,and have engineering significance for fine design of rocket structure.
作者
赵振军
臧雨晴
李强
史晓军
ZHAO Zhenjun;ZANG Yuqing;LI Qiang;SHI Xiaojun(School of Mechanical and Materials Engineering,North China University of Technology,Beijing 100144,China;High Speed Aerodynamics Institute,China Aerodynamics Research and Development Center,Mianyang 621000,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2022年第3期268-277,共10页
Journal of Vibration and Shock
基金
国家自然科学基金(51775004)
北方工业大学科研启动基金(110051360002)。
关键词
固体火箭
发射动力学
振动响应
多体动力学
弹性支撑
solid rocket
launch dynamics
vibration response
multibody dynamics
elastic support
