液体火箭压差控制交叉输送特性研究

A Study on Flow Characteristics of Pressure-Controlled Propellant Crossfeed in Liquid Rocket Systems

为提高火箭总体运载性能,利用AMEsim软件研究液体火箭交叉输送系统的动态特性,采用模块化思想,通过增压、贮箱、管路输送系统等功能模块,构建了基于AMEsim软件的交叉输送流体网络系统,并采用实验数据对压力和流量进行有效性验证;通过模拟推进剂压差控制模式下在网路系统中的流动特性,得到了交叉输送过程中管路内压力的变化特性;为保证芯级贮箱出流量最小,分析了对芯级贮箱临界压力的影响因素,得到其关于初始加注量、体积流量、飞行过载的关系。结果表明:临界压力值与助推级初始加注量、飞行过载成反比,与体积流量成正比;在临界压力下,助推级初始加注量对水击压力无显著影响;随着体积流量的增加,芯级管路水击压力逐渐减小,助推级水击压力则逐渐增加;飞行过载增大时,芯级与助推级水击压力均呈增高趋势。

A numerical model is developed to study the dynamic characteristics of the propellant cross-feeding process.The model is based on the software AMEsim and adopts the modularization idea to model the pressurization,storage tank,pipeline feeding system and other functional modules.The crossfeed model is validated by experimental data,and consistency between the calculated and measured data is found.Then,the flow characteristics and the corresponding influencing factors during the pressure-controlled crossfeed process are analyzed.The results show that there is a critical pressure to guarantee the full tank of core stage after booster separation,and the critical value is dependent on the initial propellant amount,the flight overload,and the volume flow rate.The initial refueling amount of the boost stage has no significant influence on the water hammer pressure under the critical pressure.However,an increase in the volume flow rate leads to an increase of water hammer pressure in the booster pipeline but a decrease in the core stage pipeline.When the flight overload increases,the water hammer pressures of the core stage and the boost stage show an increasing trend.