常温及低温容器充放气模型研究

Charge and Discharge Model Investigation of Vessel at Normal and Cryogenic Circumstance

为了寻求一种可准确、高效计算容器充、放气过程的方法,进而满足液体火箭动力系统工作时序设计的要求,基于开口系能量方程、理想气体状态方程以及不同流动状态下的质量流量方程,利用集总参数法编制了计算程序。利用该程序分别对一个常温氮气瓶的充、放气过程以及一个以氮气为增压介质的液氧贮箱放气过程进行了计算模拟。计算结果表明:该模型对常温容器的充放气过程有较好的计算精度;对于低温液氧贮箱来说,由于容器内存在热分层现象,放气降温过程带来的氮气相变以及压力降低后氮气从液氧的逸出等原因,使得该模型计算存在一定偏差。

In order to find out a method that could compute the vessel’s charge and discharge process precisely and effectively,and satisfy the work scheduling design of liquid rockets’propulsion system.A computation program is written based on energy equation of open system,ideal gas equation of state,mass flow rate equation at different flow state and lumped parameter method.Simulation on a nitrogen vessel’s charge and discharge process at normal temperature and a cryogenic oxygen tank’s discharge process with nitrogen pressurization are conducted by this program.The computation results show that this model has good precision when simulating vessel’s charge and discharge process at normal temperature;a certain discrepancy exists when simulating cryogenic oxygen tank’s discharge process due to the thermal stratification,nitrogen phase transition caused by temperature reduction and nitrogen precipitation from liquid oxygen caused by pressure reduction.