舰载无人机的海水动力弹射关键技术研究

To meet the launch demand of Shipborne Unmanned Aerial Vehicles(SUAV), and avoid the limited launch power of gas-hydraulic catapult, the complex structure of steam catapult and the strong electromagnetic interference of electromagnetic launch, here a new catapult scheme i.e. seawater hydrodynamic launch for SUAV is proposed. Focused on key problems such as energy conversion efficiency of nozzle jet and coupling relationship between unsteady flow of seawater jet and load motion, the mechanism and experimental investigation of seawater hydrodynamic launch are systematically carried out. The influence of characteristic parameters of nozzle on jet characteristics and energy loss is emphatically revealed. A nonlinear dynamic coupling model between gas-liquid transient flow and load motion is established. Numerical simulation related unsteady flow of seawater jet is conducted. The effect of key parameters of the ejection system on launch weight, launch speed and launch efficiency is explored. Based on multi-objective parameters and balance design criteria, the seawater hydrodynamic launch system is designed and manufactured. Parameters of the system are optimized and configurated by use of simulation combined experiment, and finally complete the 1.26 ton SUAV launch verification experiment. This project is expected to break through the technical bottleneck of traditional launch, and solve the launch difficulties of large and medium sized SUAV, of which is quitely significant to enhance China marine air force.

以舰载无人机对发射技术的迫切需求为牵引，针对现役气液压弹射发射功率较小、蒸汽弹射结构复杂、电磁弹射存在强电磁干扰等问题，本项目提出了一种新型的海水动力弹射技术方案，围绕喷嘴射流能量转化效率、海水喷射非定常流与弹射负载运动耦合关系等关键问题，系统开展海水动力弹射的机理和试验研究。重点揭示喷嘴特征参数对射流特性和能量损失的影响规律；建立气液瞬态流动与弹射负载运动耦合的非线性动力学模型，对海水喷射非定常流进行数值模拟，探究系统关键参数对弹射质量、弹射速度和弹射能效的影响机制；基于多目标参数和平衡设计准则设计并研制出无人机海水动力弹射系统，仿真结合试验实现系统参数的优化配置，最终完成1.26吨无人机模型机的弹射试验。本项目有望突破传统弹射方式的技术瓶颈，解决大中型舰载无人机的发射难题，对提升我国海基航空力量具有重要意义。

为解决无人机传统弹射发射方式的技术弊端，本项目提出了新型的海水动力弹射技术方案，综合有限元分析、数值计算和试验验证等方法，针对弹射中的关键技术开展了系统研究。1）详述了无人机海水动力弹射的具体方法，分析了动态弹射过程及影响弹射性能的约束条件；2）综合气体状态方程、能量动量方程、弹射负载力平衡方程等建立了弹射非线性弹射动力学建模，数值解析了喷嘴直径、流速系数等结构参数，以及充气压力、注水容积等工作参数对弹射反推性能的影响，明确了影响海水动力弹射动态特性的关键参数；3）系统研究了高压水定常和非定常喷射过程中，喷嘴特征参数和工作参数对射流特性和能量损失的影响规律，完成无人机海水动力弹射系统优化设计；4）研制出无人机弹射反推试验系统，理论结合试验分析了系统关键参数对喷射反推性能的影响，验证了无人机海水动力弹射方案的可行性。上述研究为后续舰载无人机海水动力弹射系统的研制，以及在型号中的推广应用，奠定了坚实的理论基础。