Small Flow High Sensitivity Rubber Diaphragm Pressure Reducing Valve Design Optimization

Pressure reducing valve is widely used in national economic construction and national defense construction.In the aerospace field it has a particularly wide range of applications such as environment control and life support system in space station,satellite propulsion systems and solid or liquid rocket attitude control engines.In the design process of the pressure reducing valve,the rigidity of the rubber diaphragm is often neglected,and the effective area of the rubber diaphragm is generally determined by an empirical formula instead of an experimental test.The effective area of the rubber diaphragm calculated with the empirical formula is deviated from the actual value,which makes the outlet pressure of the relief valve climb,and the deviation from the design value is too large.In this paper,firstly,the mathematical model of the pressure reducing valve is established according to the pressure balance valve stress balance equation,mass flow equation and flow continuity equation.From the mathematical model,it can be seen that the rigidity and effective area of the rubber diaphragm need to be measured through tests.This subject has measured the rigidity and effective area of the rubber diaphragm through the equipment.It can be seen from the test results that when the deformation of the rubber diaphragm is 0-3.25 mm,the stiffness of the rubber diaphragm is 0.9-3.7N/mm.The stiffness and effective area of the rubber diaphragm measured by the test were substituted into the AMESim simulation model,and the dynamic characteristics of the pressure reducing valve were simulated and analyzed using simulation software.The orifice diameter,spring stiffness,and valve core quality of the pressure reducing valve were studied.Based on the results of simulation analysis,the pressure relief valve was optimized.The performance reliability calculation of the pressure reducing valve after the design optimization is performed to verify that it meets the design requirements.Finally,the sensitivity analysis of the pressure reducing valve was carried out,and it was concluded that among the three influencing factors of orifice diameter,static pressure flow and adjusting spring stiffness,adjusting the spring stiffness is the most important factor affecting the size of the static characteristic index.This subject for the future to further optimize the design of the valve,provide theoretical and experimental parameters.