减压器动态仿真的有限体积模型

Finite volume model for numerical simulation on dynamic process of pressure reducing regulator

关键词:  减压器  有限体积法  动态特性  数值仿真

Key words:  Pressure reducer  Finite volume method  Dynamic characteristics  Numerical simulation

摘要:

通过对一维理想气体流动的有限元状态变量模型推导过程的拓展,获得了适用于变体积容腔的气体容积模型,并结合气体管道、气体阀门的有限元状态变量模型,通过对三者的组合运用发展了一种可仿真气体减压器动态工作过程的有限体积模型。采用此模型分别对某逆向卸荷膜片式减压器和某贮箱增压系统所用减压器进行了动态工作过程的仿真,前者仿真结果的稳态值与早期文献的实验数据和仿真结果相一致,表明有限体积模型的稳态精度合乎工程需要;后者的仿真获得了减压器各个腔室状态参数和阀芯开度的响应曲线,表明贮箱增压过程可以分为启动段、稳定段两个阶段,同时表明在理想气体绝热流动的假设下节流前后温度基本不变。数学模型和建模方法显示出良好的有效性和通用性。

Abstract:

A gas volume model suitable for vessels with variable volume was obtained by developing the finite element state-variable model of one-dimensional ideal gas flow.Based on the model,combining with the finite element model of gas pipe and gas valve,a finite volume model(FVM) was put forward to simulate the dynamic process of gas pressure reducing regulator.Then by employing FVM,two kinds of regulators were simulated.Tie simulation of a converse and unloading regulator with diaphragm shows that FVM can satisfy steady precision requirement by comparison with the experimental and simulation data in earlier literature.The simulation of a regulator in tank pressurization system gave the response curves of opening of valve core and state variables in every cavities,which show that the pressurizing process can be divided into two stages including start-up and steady.The curves also indicate that temperature in low-pressure cavity is almost the same with temperature in high-pressure cavity for one-dimensional ideal gas adiabatic flow.Accordingly,the mathematical model and the method of modeling are validated to be effective and versatile.