Research Of The Regulating Characteirstics And Noise Analysis In Turbine’s HP Bypass Valve

HP bypass valve of turbine is the most important part in the HP bypass system. The failure of the valve will threaten the safe-efficient processing and sometimes cause the stop and accidents of the Turbine. So the controls of the high-pressure bypass valve become critical.Control valve is indispensable control equipment in kinds of fluidal equipment and has the extensive application in the national economy.While in the past,more attention was paid to the view of machinery.Due to complicated inside structure of control valve and plenty of flow pattem,Adjusting performance,lower strepitus,energy conservation and reduce cost it has theoretical meanings and practical value to study control valve inside flow on the view of hydraulics.Main contents of this paper are as follows:The first:This topic background and significance was expand, and domestic and foreign research situation and development trend of control valve, same time, points out the research emphasis, takes method and the feasibility of the scheme.The second:Steam turbine bypass system and control valve were introduced systemic, and the basic fluid mechanics knowledge, hydraulic knowledge and the use of the CFD technology were stated succinctly.The third:the regulator flow area and flow of the analytical mathematics equation can be derived by considering the density change of compressibility conditions. And presents the relationship of the compressible fluid velocity and the Mach number, and on this basis, the ideal of flowing characteristics was studied respectively with fast open type, linear, and parabola.The fourth:first, the different opening of the control valve fluid3d model was established by PRO/E, divided mesh by GAMBIT, and internal flow field simulation analysis of control was based on fluent software of the CFD technology, the results show that different opening valve inlet pressure loss under pressure distribution characteristics, the pressure cloud chart and the velocity distribution map. Then it is concluded that the actual flow characteristics by means of the above analytic mathematic type, and calculation and simulation of the numerical comparison and analysis. Finally, the dynamic characteristics of flow to the regulator made a step analysis research through MATLAB/Simulik install the system simulation model with components of control valve used for different steem system.The fifth:based on the dynamic characteristics of the influence factors of the regulator simulation research, were studied pressure difference, temperature, sleeve structure, materials, pressure of spray water to the effects of noise, the major effect of the noise that regulator from valve differential pressure and flow velocity and after, other factors affecting small, and gives some measures to eliminate noise.The sixth:this thesis summarizes the work and achievements and look forward to the next step of research.