Numerical Simulation Of Internal Flow And Test Research Of Cut-off Valve

Cut-off valve is one of the most basic components in fluid power transmission and controltechnology. Also cut-off valve internal flow field has a directly influence of its characteristic.What’s more, the flow characteristics of spool in cut-off valve have a big effect in the process ofopening and closing. In order to design reasonable spool structure of cut-off valve, it has animportant significance to master fluid mechanism of flow passage in saving energy and reducingconsumption. And the rapid development of CFD technology that provides powerful means forfurther researching complex flow field in cut-off valve. Therefore, in this paper, to fully analyzecut-off valve internal flow field characteristic, the conventional and newly designed spools thathave different motion conditions in cut-off valve are carried out by using a method of numericalsimulation and test research. And then, external characteristic of cut-off valve is researched.Specific contents are as follows:1. With the optimization design of spool structure, a newly designed spool that hasmulti-seal and throttle down and decompression structure is generated in this paper. According tocut-off valve’s actual structure and parameter, and combining with the numerical model, the3-Dmodels which include valve body, valve bonnet, spool and connecting parts are obtained byusing software Pro/E. Based on software CFD, flow passage is generated by using unstructuredmulti-block grids of the former processing software Gambit.2. The fundamental equations are Reynolds averaged Navier-Stokes equations usingstandard turbulence model for solving turbulence flow. For this, numerical simulationthat includes pressure, velocity and streamlines distribution is performed at several valve modelsboth conventional and newly designed cut-off valve under the different working condition. And anumerical analysis of results contrast is carried out between conventional and newly designedvalve.3. The unsteady3-D numerical research is simulated in the process of spool’s opening andclosing. For this, to define speed of spool, a dynamic grid technology is adopted by using Fluentof User’s Define Function. Numerical simulation results of conventional and newly designedcut-off valve have an important practical significance to analyze the spool structure and design offlow passage. 4. The test research of external characteristic is carried out at the different spool openingposition and working condition. The performance curves are obtained and compared with theresult of numerical simulation.