Development And Structural Optimization Analysis Of High Temperature Axial Flow Regulating Valve

Axial flow regulating valve as an important branch of the valve,widely applied in aerospace equipment test pipeline,can be used in high flow rate,high pressure difference and other conditions,its function is open and closed with load,can work at any position in the stroke adjust the flow and pressure,control the quality of the flow field.With the development of China’s aerospace industry,the parameters of the intake system of the aero-engine test stand are constantly improving,so the development of large diameter and high temperature axial flow regulating valve demand arises.However,due to the lack of DN1000 and above large diameter valve flow resistance coefficient and flow characteristics test device in domestic,the valve flow can not be accurately selected;At the same time,because the high temperature internal heat test system is relatively complex,domestic scientific research institutes do not have the ability to carry out high temperature hot state test of the valve,the key parts of the fit clearance is not appropriate,will cause the operation of the valve under high temperature to be stuck.In this paper,axial flow regulating valve as the research object,aimed at its regulating characteristics,combined with high temperature performance index,carried out the design and development of regulating valve.The axial flow regulating valve is studied deeply from the aspects of valve structure optimization design,flow field simulation analysis,thermal gap compensation theory and thermal-solid coupling analysis,and the regulating valve is developed which meets the requirements of the intake system of aero-engine test bed.The main work of this paper is as follows:(1)Carry out the structural optimization design of high temperature axial flow regulating valve.According to the working condition of the control valve parameters and performance indicators,based on the original design of a valve company,analyze and optimize the key components-valve cage and guiding mechanism,the reasonable and reliable structure form under high temperature condition was determined.(2)Carry out the flow field characteristics analysis of high temperature axial flow regulating valve.According to the design drawings,using Solidworks software to establish a THREE-DIMENSIONAL model and analyze the internal flow field of the axial flow regulating valve in different opening degrees,Obtain the flow of different opening degrees and draw the linear adjustment characteristic curve,and obtain the pressure and velocity cloud diagram under the working condition parameters.(3)Carry out the temperature field analysis of moving pair of high temperature axial flow regulating valve.The thermal stress is mainly caused by the temperature gradient of the moving pair,and the temperature gradient function is a function of the axial and radial dimensions and time of the parts.The unsteady temperature function of the moving pair was derived when the temperature was 500℃ and the temperature rise rate was 30℃/min,and the minimum temperature gradient time value of the moving pair was obtained,which is verified by the non-transient temperature field analysis module of finite element simulation,The results show that the results of the two methods are consistent.(4)Carry out thermal gap compensation analysis.Based on the thermoelastic displacement method,the thermal gap compensation formula of the moving pair was derived,and the relation curve between the displacement value of the contact surface of the moving pair and time is obtained through the nonlinear mechanics module of the finite element simulation.Analysis shows that there is not much difference between the maximum value and the calculated value of the compensation formula,and the time node at which the displacement tends to stabilize is equivalent to the calculated minimum temperature gradient time.To sum up,the flow field characteristics analysis、the temperature field analysis of the moving pair and the thermal clearance compensation analysis of the moving pair and the research methods carried out in this paper have a good reference for the optimization design of high temperature axial flow regulating valve.