车载冷发射系统多刚体动力学快速仿真研究

为了满足发射动力学快速分析的需要,采用多刚体动力学的绝对坐标方法以适应发射车约束复杂和变拓扑结构的特点,针对车载冷发射系统的典型结构和弹射物理过程,建立并应用了9自由度快速仿真模型。与ADAMS和ABAQUS仿真对比表明,本文计算的车架后支腿载荷偏差不超过4%,而仿真时间只有ADAMS的7.1%和ABAQUS的0.004%,能够快速有效地分析系统的动态特性。通过实例研究了发射管底座-车架支腿载荷比的动态特性和附加载荷分配因子对该载荷比均值及发射管口最大位移的影响。结果表明,发射管底座-车架支腿载荷比在发射过程中逐渐增大并达到稳定值,附加载荷分配因子决定了发射管内弹道压力载荷通过发射管底座和发射车支腿分散传递到地面的载荷分配比例,并且存在最佳附加载荷分配因子,能使弹体的弹射起动过程对系统的扰动影响最小。

Fast simulation on rigid multibody dynamics for vehicular cold launch systems

In order to meet the rapid analysis requirements of launch dynamics, the absolute coordinates method of rigid multibody dynamics was used to fit the characteristics of complex constraints and changing topological structure of the vehicular launch systems. A fast simulation model with nine degrees of freedom was established and applied for typical vehicular cold launch systems. By comparing with ADAMS and ABAQUS, it shows that the maximum deviation of the loads of the rear outrigger is less than 4%, the consumed time is 7.1% of ADAMS and 0.004% of ABAQUS, and the current simulation model is effective and convenient to simulate the system dynamic characteristics. An actual example was adopted to investigate the dynamic characteristics of the load ratio of launch tube base-chassis outrigger and the influences on the average load ratio and the maximum displacement of launch tube mouth from an adjunctive load distribution factor. The results show that the load ratio of launch tube base-chassis outrigger increases gradually and then keeps constant approximately in the ejecting process, the adjunctive load distribution factor determines the load distribution proportions between the launch tube base and chassis outrigger by which the interior ballistic pressure load in the tube is transmitted to the ground, and the most suitable adjunctive load distribution factor exists which makes the disturbance on the system caused by missile ejection motion least.