喷射泵-液环泵联合抽空液氧过冷方案仿真研究

Simulation of liquid oxygen sub-cooling process using ejector/liquid ring pump combination vacuum system

采用微元方法对液氧抽空过冷的传热传质过程进行仿真模拟,分析了喷射真空泵工作流体流量和压力、最低被引射流体压力和初始液位对于液氧抽空过程的降压特性、抽空时间及剩余液位的影响,获得喷射真空泵与液环泵联合抽真空的液氧过冷系统最佳工作条件:针对本研究液氧贮存系统,当储罐初始液位95%时,采用喷射真空泵工作流体流量为0.25 kg/s、喷射压力为5 MPa,最低被引射流体压力为34.35 kPa,后采用抽速5 m^(3)/min的液环泵,可以18小时内将60 m^(3)的液氧储罐抽空至10 kPa,且剩余液位达75%以上。

In the present study,a microelement method based on vectorized programming is used to simulate the heat and mass transfer process of liquid oxygen vacuuming and sub-cooling.The flowrate and pressure of the working fluid for the jet vacuum pump,the minimum ejected fluid pressure and the initial liquid level of the liquid oxygen are analyzed to investigate the influences on the vacuum pressure reduction characteristics,the duration of vacuum extraction and the remaining liquid level of the liquid oxygen tank are investigated in the simulation.The optimal operating conditions of the liquid oxygen sub-cooling system obtained.For the present liquid oxygen storage system,if the initial liquid level of the storage tank is 95%,the working fluid flow rate of the jet pump is 0.25 kg/s,the injection pressure is 5 MPa,the minimum vacuum pressure of the ejector is 34.35 kPa,and a liquid ring pump with a vacuuming capacity of 5 m^(3)/min is used,a liquid oxygen tank of 60 cubic meters can be vacuumed to 10 kPa within 18 hours,and the remaining liquid level is above 75%.