【作者】 郑丽；

【导师】 沈赤兵； 李清廉；

【作者基本信息】 国防科学技术大学 ， 航空宇航科学与技术， 2007， 硕士

【摘要】 本文以自主研制的大流量减压器为研究对象,采用理论分析、试验和零维仿真方法,研究了减压器的静态特性、稳定性和响应特性;将减压器内部流场的演化和活动组件的运动耦合起来,建立了一种基于动态流场仿真的减压器特性研究方法。将大流量减压器应用于试验,检验了结果的适用性。考虑气动力和膜片弹性力等非线性因素的影响,建立了减压器的零维非线性数学模型,通过与试验对比验证了模型的正确性。研究了减压器的压力特性、流量特性和压力偏差特性,分析了阀芯直径、膜片面积和膜片弹性系数等结构参数对静态特性的影响规律。建立了减压器的传递函数模型,分析了入口压力、流量、控制气压力对稳定性的影响,研究了阀芯直径、控制腔体积、出口腔体积、阻尼腔体积、阻尼孔面积和控制气入口面积等结构参数对稳定性的影响规律。对减压器整个工作过程,包括充填过程、开启过程和关闭过程进行数值仿真,分析了减压器各工作阶段的响应过程。研究了入口压力和流量等工作参数,以及阀芯直径、控制腔体积、出口腔体积、阻尼腔体积、阻尼孔面积和控制气入口面积等结构参数对响应特性的影响规律。基于成熟软件平台,发展了动网格技术和流固耦合仿真技术,分析了减压器内部稳念流场,发现了超临界和亚临界两种流场。得到了减压器的流量系数曲线。仿真了减压器开启过程和关闭过程的内部流场演化过程。分析了内部过程和特性之间的关系。采用基于内部流场动态仿真的方法研究减压器的特性。从内部流场的角度分析了减压器的静态特性,讨论了入口压力变化和流量变化对减压器开启过程响应特性的影响,研究了动态入口压力和动态控制气压力条件下减压器的稳定性。揭示了影响动态过程的内部因素。通过在流量计标定试验和燃气发生器试验中的应用,验证了研究结果的适用性。更多还原

【Abstract】 The paper studies the static characteristics, stability and responding characteristics for our large flux pressure reducing valve with two methods. One is experiment and zero-dimension simulation, the other one is based on the simulation of the transient flow field, which couples the internal flowfield and the movement of the valve core.Considering the two nonlinear factors------gas dynamic forces and diaphragmelastic forces, the paper develops a nonlinearity characteristics mathematical model for the pressure reducing valve.The static pressure characteristics, static flow characteristics and pressure derivation characteristics are researched. And get the conclusion that the computed results are consistent with the experimented results .On the base of theses, the paper analyses the influence of the diameter of the valve core, the area of the diaphragm and the spring modulus of the diaphragm to the static characteristics.After founding the transfer function, the paper analyses the influence to the stability of the inlet pressure, mass flux, the control pressure, the diameter of the valve core, the volume of the outlet cavity and control cavity, the volume of damping cavity, the area of the damping hole and the control hole.Based on the right model, the paper then studies the responding characteristics of the filling process, startup and shutdown processes. The influence to responding characteristics of the inlet pressure, mass flux, the diameter of the valve core, the volume of the outlet cavity and control cavity, the volume of damping cavity, the area of the damping hole and the control hole are researched.Developing the dynamic mesh and fluid-solid coupling simulation technique, the paper studies the steady flow field, and discovers two types flow field, then researches the discharge coefficient.Based on the simulaton of the transient flow field of startup and shutdown processes, it studies the relation of the interior process and the characteristics.Adopting the method of the simulaton of the transient flowfield,the paper analyses the static characteristics,and discusses the influence to responding characteristics of the inlet pressure and flux rate,studies the stability of the dynamic inlet pressure and control pressure.The usability of the research results is verified by the application to gas generator hot-fire tests and the certification tests of the mass flowrate.更多还原