Flow Coefficient Analysis for a Globe Valve by using CFD

The valve selections criteria involves determination of valve coefficient, flow characteristics, shutoff requirements, body end connections, pressure classes, face to face dimensions, body and trim material selections, gasket and packing selection and process flow parameters. The measurement commonly applied to the valves is the valve coefficient (Cv) which is also known as flow coefficient. When selecting a valve for a particular application, the Cv is used to determine the valve size that will best allow the valve to pass the required flow rate, while providing stable control of the process fluid. This paper presents the research of Flow Coefficient analysis for a Globe Valve by using Computational Fluid Dynamics (CFD). The globe valve is the most commonly found control valve in the process industry due to its simple design, versatility of application, ease of maintenance and ability to handle a wide range of pressures and temperatures. Globe valves are used in both gas and liquid services. The flow system with Globe valve is complex structure and has non-linear characteristics. In this paper, three-dimensional numerical simulations and experiment were conducted to observe the flow pattern and to measure valve flow coefficient and flow fluctuations when globe valve with different flow rate and uniform incoming velocities were used in a pipeline system. These results not only provide user with the access of understanding the flow pattern of the Globe valve with different flow rate and velocities, but also were made to determine the methods which could be adopted to improve the performance of the valve.