Investigation of a standard gate valve in terms of flow rate, opening distance and wedge angle with CFD

Abstract

Gate valves provide sealing with metal-to-metal friction. When the right interior parts are selected, and the production is not made according to the proper design criteria, internal leaks occur in the valves in the medium term. Considering the ideal pressure, velocity equations and designs suitable for the process can be realized by determining the nominal pressure and velocity curves. This study designed a standard gate valve with 8-inch connection dimensions. Computational Fluid Dynamics (CFD) method investigated split, flexible, and solid wedge types of the designed valve, 0.5, 1, and 2 m/s flow velocities for zero, four and five-degree wedge closing angles and 20 mm, 40 mm, 60 mm, 90 mm, and 120 mm opening wedge positions. Ansys Fluent software was used for the analyses. Mesh optimization was performed for the ideal mesh number and analyzed according to the ideal mesh number. The k-Epsilon turbulence model was used for simulations. The same situations were repeated for a parallel wedge (0-degree wedge seating angle). The lowest pressure distribution and pressure loss occurred in the parallel wedge compared to the opening position of other types of wedges. The best gate type obtained from the analysis results was determined, and an experimental tightness test was performed. It can be said that the soft seat gate valve, designed according to the results of the sealing test, gives approximately 2.5 times more opening-closing life than the metal gate valve, thus reducing the maintenance-repair costs.