双级气体减压器稳定性影响因素数值分析

针对应用于飞行器增压系统的双级气体减压器,从单级气体减压器的有限体积瞬变仿真模型出发建立了其数值模型,并搭建了双级减压器特性研究系统的模块化仿真模型.通过大量的时域仿真研究了某两型具有细微设计差异的减压器各结构参数对其工作稳定性的影响规律,并比较了两者间的异同,随后根据工程需要,选取减压器二级阀芯运动速度的样本方差作为稳定性指标,重点研究了某减压器二级阀芯质量、低压腔体积、反馈腔体积及膜片刚度变化对稳定性的影响程度.仿真结果表明,设计人员可以优先减小该减压器的二级阀芯质量或增大膜片刚度从而更快地改善其稳定性,该分析方法可以帮助相关设计人员以最小的代价获得满足工程要求的结果.

Numerical analysis of influence factors on stability for dual-stage gas pressure reducing regulator

A numerical model of a dual-stage gas pressure reducing regulator, which is used in an aircraft pressurization system, was established on the basis of finite volume transient model of single-stage gas pressure reducing regulator. A modularization simulation model was also set up for performance study of dual-stage pressure regulator. The influences of different structural parameters on the stability of the two regulators which have tiny structural differences were illustrated by a series of numerical simulation, and their results were compared and analyzed. According to practical needs, the sample variance of II-stage valve spool velocity was chosen as the stability index, numerical analysis was then conducted on the influence factors including the II-stage valve spool mass, the II-stage low-pressure cavity volume, the II-stage feedback cavity volume, and the II-stage diaphragm stiffness. Results show that designers can decrease the II-stage valve spool mass or increase the II-stage diaphragm stiffness to improve the stability of the regulator. The study can help designers to meet the engineering requirements with minimum expenditure.