机载水平后向弹射同时离轨动力学响应研究

Dynamic response of small rockets airborne horizontal backward ejection simultaneously off orbit

为解决小型火箭自力发射消耗燃料较大、运载能力较弱的不足,进一步提高小型火箭运载能力,在现有冷弹射技术的基础上提出一种机载水平后向弹射方法,实现小型火箭机载平台冷弹射发射,以减小发射所需燃料、提高火箭运载能力。基于发射动力学理论,建立火箭机载水平后向弹射动力学模型,实现多工况机载水平后向弹射有限元数值仿真,研究机载平台后向弹射的弹射机理和规律。研究结果表明,以梁单元和壳单元为主的有限元模型模态振型一致,特征频率相近,各阶频率相差在10%以内;进一步研究表明,飞机攻角对弹射速度和加速度影响较小,但对角位移、角速度影响较大,飞行攻角不会影响火箭分离过程的安全性;载机振动对弹射动力学响应影响较小,且不会影响分离过程的安全性。

Here,to solve shortcomings of larger fuel consumption and weaker carrying capacity in self-powered launch of small rockets,and further improve their carrying capacity,an airborne horizontal backward ejection method based on existing cold ejection technology was proposed to realize cold ejection launch of small rockets from airborne platform,reduce required fuel for launch and improve rocket carrying capacity.Based on the theory of launch dynamics,the dynamic model for rocket airborne horizontal backward ejection was established.Finite element numerical simulations were performed for airborne horizontal backward ejection under multiple operating conditions to study the ejection mechanism and laws of backward ejection from airborne platform.The study results showed that modal shapes of finite element models mainly consisting of beam elements and shell elements are consistent,they have similar modal frequencies and frequency difference for their each order is within 10%;flight attack angle has a less impact on ejection velocity and acceleration,but a larger impact on angular displacement and angular velocity,flight attack angle can’t affect the safety of rocket separation process;carrier vibration has a less impact on ejection dynamic response and can’t affect the safety of rocket separation process.