航行体水下高膛压与高速发射载荷特性

Load Characteristics of High Chamber Pressure and High Speed Launch of Underwater Vehicle

水下高膛压高速发射航行体后形成的多相流场复杂多变,产生的载荷影响尚未明确。针对某小口径水下航行体高膛压、高初速冷发射过程,开展发射载荷特性研究,分析航行体发射过程中内弹道阶段、溢出燃气与水相互作用阶段、水锤效应阶段的流场特性与力学特点。基于多相流模型和动网格方法,建立航行体水下高速冷发射过程数值模型,进行气-汽-液多组分数值仿真,对不同时期发射筒的载荷特性及其成因进行分析。研究结果表明:水下航行体高速发射载荷主要来源于内弹道过程与水锤效应,航行体出膛后筒内燃气溢出造成的低压区产生载荷较小;与低膛压、低初速发射工况不同,高膛压发射工况下筒内气体高速大量溢出,水锤效应压力峰值的幅度衰减明显。

The multiphase flow field formed behind a vehicle under high-chamber pressure and high-speed launch in water is complex,and the load effect is not clear yet.The launch load characteristics of a small-caliber underwater vehicle during cold launch under high chamber pressure and high initial velocity were investigated.The flow field and dynamic characteristics during interior ballistics,interaction between overflow gas and water,and hydrodynamic ram effect stage during the launch of the vehicle were analyzed.A numerical model of the high-speed cold launch process of the underwater vehicle was established,while a numerical multicomponent gas-vapor-liquid simulation was performed using a multiphase flow model and a dynamic grid approach.The load characteristics of launcher and their causes in different phases were then analyzed.The results showed that:large impact loads were mainly from the internal ballistic process and the hydrodynamic ramhydrodynamic ram effect,while a relatively small load was from the low-pressure area caused by overflowing gas;more specifically,the hydrodynamic ram hydrodynamic rampeak pressure decreased significantly because the mixed gas spilled out in large quantities under high chamber pressure,which was different from the low chamber-pressure launch condition.