Numerical Calculation And Analysis Of Control Valve Of Steam Turbine

The regulating valve that this paper discussed and analyzed of is a device used for controlling fluid flow of steam turbine, it is widely used for steam turbine equipment. In a steam turbine, regulating valve characteristic influence the economy and safety of unit, the unit stable operation plays an important role in.This article is on the base of reading lots of literature, combined with his long engaged in steam turbine governing experience, for a variety of regulating valve for the use and study of research and study, the unit operation process of the various problems, then regulating valve problems were studied and discussed.In the middle and small unit, control valves to be used in groups, especially in the high pressure section of each valve, affect a certain number of nozzle. According to the user site to provide steam turbine regulating valve operation data and feedback information, adjusting valve of valve disc matching form and adjust the opening timing will cause an unreasonable unit operation instability, sometimes set in certain conditions can cause severe fluctuations, affecting the safe operation of the machine group.Be based on the different users demand, in some conditions, the turbine set will be worked in low load conditions, which would cause the unit load not conform to diagram requirements.The article is aimed at these problems, the use of the CFD software on regulating valve for flow field analysis, and the use of the CFD software and three-dimensional modeling software is introduced, analyzed the three-dimensional numerical simulation model is established and the calculation steps of the process.First of all, was built by SolidWorks ball and pear shape regulating valve of the3D model, the import to the Gambit grid, the use of FLUENT3D numerical simulation and calculation.As to the research and analysis to the case of more accord with actual, selection of medium temperature and medium pressure steam parameters as boundary conditions and physical properties of. The velocity vector, the Maher number, pressure contour map image data.Through the data analysis of the results, we can see, the two valve plate convergence curve, velocity distribution, pressure changes in the different, from, to identify the regulating valve group selection theory. Through analysis, can see, the actual operation in the state of a great degree and regulating valve selection related. From the data, we can analyze the actual operation, the vibration and damage causes. In the valve disc up process, the valve disc below the emergence of larger aperture area is the influence of valve disc vibration and load fluctuation, the larger hole area with obvious recirculation characteristics, is not conducive to the stability of steam flow, affect the flow capacity. Therefore, this article through the detailed analysis to optimize the control group selection using, as the regulating valve structure is optimized further provides testing support.