考虑气动载荷条件下的高速滑轨结构参数对撬轨动力响应的影响分析

EFFECT OF STRUCTURE PARAMETER ON DYNAMIC RESPONSE OF HIGH SPEED ROCKET SLED TRACK SYSTEM UNDER THE CONDITION OF CONSIDERING A ERODYNAMIC PAYLOAD

火箭橇在亚音速、跨音速、超音速条件运行时引起的动力学问题是高速滑轨设计制造重点考虑的问题。结合某撬轨系统,建立气动作用下撬轨动力分析有限元模型,研究钢轨、轨道梁和扣件参数对撬轨动力响应影响关系,探讨高速滑轨结构参数取值原则。研究表明:在400 m/s速度下滑撬垂向加速度约为1g(g=9.8 m/s2);钢轨刚度的改变对系统动力响应影响比较大;目前设计所采用的轨道结构刚度较为合理,扣件刚度在满足1 200 kN/mm～2 000 kN/mm范围条件下可适当优化。

The dynamic response of rocket sled moving at subsonic, transonic and supersonic speeds is much concerned with in the design and manufacture of high-speed track for launching the rocket. A dynamic analysis finite element model for a sled-rail system is developed. The model is used to study the influence of the parameters of the rail, track beams, rail fastenings on the dynamic response of the rocket sled. And also the principles of selection and use of the important structural parameters of the high-speed track are discussed. The obtained results show the vertical acceleration of the rocket sled is about lg（g = 9. 8 m/ s2 ） at its speed of 400 m/s. The effect of the track stiffness change on the dynamic response is significant. The section of the track stiffness in the present structure design is reasonable and reliable. There is a possibility of further optimizing of the fastening stuffiness of 1 200 kN/mm - 2 000 kN/mm. The results of research will provide the useful guidance to the track designers of high-speed rocket sleds.