运载火箭注气式蓄压器联通孔流量特性数值仿真研究

Numerical Simulation Study on Flow Characteristics of Communication Port in a Launch Vehicle Gas-Filled Accumulator

关键词:  液体运载火箭  推进剂输送系统  蓄压器  联通孔  流量系数

Key words:  Liquid launch vehicle  Propellant feed system  Accumulator  Communication port  Flow coefficient

摘要:

运载火箭注气式蓄压器存在主流垂直流动对联通孔内水平流动的影响，如果采用一维经典流体力学方法计算联通孔流量系数会产生很大误差。针对这一问题，采用计算流体力学方法，在不同主管流速的条件下，对单个联通孔内的流体流动进行三维稳态数值仿真研究。研究表明，联通孔流动同时具有T型三通管流动和孔板流动的特点。受主流垂直流动的影响，联通孔内流动呈现出明显的不对称性和非线性特征，流速比小于-2.54或大于1.29时的流量系数相对变化超过15%。根据仿真结果，给出了考虑主管流速的联通孔流入和流出流量系数拟合式，以及流量系数相对变化量和流速比的关系式。

Abstract:

The vertical mainstream flow has an impact on the lateral flow inside the communication port in a launch vehicle gas-filled accumulator， which may cause a marked deviation if the classical one-dimensional hydrodynamics method is used to calculate the flow characteristics of the communication port. The problem is studied by conducting three-dimensional steady-state numerical simulation on flow inside a single communication-port with different mainstream velocities， using Computational Fluid Dynamics method. It is found that the flow inside communication port has the characteristics of both T-branch tube flow and orifice flow. Affected by the vertical mainstream flow， the flow inside communication port shows obvious asymmetry and nonlinearity， as the relative variation of the flow coefficient may exceeds 15% when the velocity ratio is less than -2.54 or greater than 1.29. Based on these simulation results， fitting formulae are given to estimate the charge and discharge flow coefficients of the communication port with different mainstream flow velocities， also the relationship between the relative variation of the flow coefficient and the velocity ratio.