Design, Measurement and Simulation Studies on Pneumatic Pressure Control Valves

• Main Authors: Chen, Yu-Li, 陳郁澧
• Other Authors: 謝宗翰
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/72873548424318306508

博士 === 逢甲大學 === 機械與航空工程博士學位學程 === 105 === This study was divided into two stages: the analysis of flow field characteristics within a proportional valve and the designing and testing of a pneumatic proportional valve. In the first stage, we considered the pressure-based finite volume method to solve Reynolds-averaged Navier-Stokes equations for three-dimensional steady flow, which enabled us to simulate and to conduct a preliminary examination of the flow field characteristics within a proportional valve. In valve grid design, we used a three-dimensional hybrid grid configuration for grid adjustment and local encryption in the overall grid and boundary regions and thereby enhance calculation precision. For spatial discretization, we adopted the SIMPLE algorithm coupled with the parameters pressure and velocity. During the initial numerical calculation process, we adopted a first-order discretization format to obtain preliminary results with lower precision. We then used these results to derive the second-order discretization solution and increase the precision of flow field calculations. To consider the viscosity of the complex flow field, we employed the k- shear stress transmission (SST) two-equation turbulence model, which is suitable for characterizing free shear flows and turbulent flows in the near-wall boundary layer. Boundary condition settings were based on the operating conditions of the valve, and inlet and outlet experiment data served as the initial conditions in internal flow field calculations. Furthermore, we constructed a novel pneumatic measurement system that can measure the near-wall pressure in the flow channels within a proportional valve during experiments. We conducted an in-depth comparison and analysis of the measurements and simulation results to verify the reliability of the simulation results.