| The wind tunnel test is the most widely used to provide important aerodynamic data for aircraft design.The wind tunnel flow field quality directly affects the authenticity of the test data,and it is the basic requirement for the aerodynamic test.During intermittent wind tunnel operating,the supply pressure falls,the flow field will be poor,the test data become bad.The pressure-regulating valve can realize the rapid adjustment and precise control of wind tunnel’s pressure and Mach number,the flow field performance stable,keep device operating normally,and avoid the pressure decaying and airflow instability effectively.Performance of the wind tunnel is determined by the function of pressure-regulation valve directly,which is key to improve quality of flow field and the capability of wind tunnel.Therefore,developing the pressure-regulating valve is the key technology of wind tunnel design and construction.In this paper,developing the pressure-regulating valve is the target.Detail Research on its pressure-regulation characteristics,The valve is studied in detail from the aspects of aerodynamic scheme design,theoretical calculation,design structural,simulate flow field of valve,structural analysis and optimized,vibration and performance test.The valve that can make the flow field up to the national military standard.Thesis mainly completed the following research work:(1)Introduce theory of pressure-regulating valve,finish the aerodynamic design and theoretical calculation.According to the wind tunnel performance,the pneumatic scheme of valve is selected,introduce the aerodynamic design method,the characteristic parameters of valve are determined,and the theoretical curve of the pressure-regulating surface coordinate and the characteristic is calculated.(2)The valve structure design.Based on the aerodynamic design and performance index requirements of the pressure regulating valve,implemented designing the valve’s structural,design the important parts,such as the valve body,valve spool,driving mechanism,guiding device and the sealing device were completed,also the kinematics of the valve was implemented.Simulating and analysis of the valve core structure and the guiding device are compared and optimized,and a reasonable function realization method and a reliable structural scheme are determined.(3)Numerical simulation of the flow field.Based on the valve’s structural,the flow field model of valve is established by CFD.The flow field is simulated under different working conditions,and the distribution of pressure and velocity of the airflow in the valve is obtained.The inside of the pressure regulating valve was mastered.The flow characteristics of the medium and the aerodynamic load of the important parts in the valve are also provided for the optimization of the pressure regulating valve structure and the performance test.(4)Conduct overall static strength and modal analysis,and optimize the structure.The finite element was established by Abaqus software.The finite element method was used to calculate the overall static and modal analysis of the pressure regulating valve.The stress and overall deformation of the structure under different operating conditions were obtained.The important components such as the moving valve core were mastered.Dynamic characteristics,combined with actual operating conditions,vibration analysis of the valve structure,simulation and comparison of each structure,and proposed an effective structural optimization program.(5)Realized the valve’s structure,and pressure-regulation test.According to the simulation analysis results,the final structural scheme of the valve is determined and completed.The valve is connected to the wind tunnel system,and the vibration response test and dynamic pressure regulation characteristic test are carried out to obtain the dynamic characteristics of the structure.The characteristics are in good agreement with the theoretical calculations,and the valve structure is safe and reliable.During finish this work,the design and implementation of the wind tunnel pressure regulating valve was completed and successfully put into use.From the theoretical design and experimental verification,the wind tunnel pressure regulating valve scheme is feasible and reliable,and can realize the precise regulation of wind tunnel pressure.Its excellent pressure regulating characteristics realize the wind tunnel flow field quality reaches the advanced level of the national military standard.The foundation for the improvement of wind tunnel test capability has been laid.The successful development of the pressure regulating valve has improved the technical level of wind tunnel equipment design,and provides reference and reference for similar valve design in the future. |
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