Study of flow field variables in a pressure reducing valve

Pressurized water valves are required in industrial applications ranging from steel industries to manufacturing plants where cooling is highly required. High water pressures are the most common requirement to descale oxide layers formed during steel production. The water passes through pumps, piping systems and valves before it flows out through nozzles. Such a high pressure requirement is generated from pumps and regulated by means of valves. The directional checking and ON-OFF regulation are the major jobs a valve should perform satisfactorily. The fluid properties are governed by mass, momentum and energy conservation as defined by Continuity, Navier- Stokes and Energy equation. The high pressure drop along the neck of the venturi induces cavitation problems which lead to failure over time. Variation of several fluid properties like pressure, wall shear stress can be seen as the fluid flows through the valve. The high pressure fluid at the upstream region goes through the downstream region from the nozzle when the given valve allows to exit. The sharp bends and turns inside the valve causes several properties of water to change throughout its flow domain. The failure being observed on a high pressure water flow passage on a specific geometrical cross section from one of the local companies will be evaluated from the computational analysis. Lately, a baffle system was modeled in 2D as one of the capstone design projects for an undergraduate student. The main objective of this system was to attain a pressure drop within the channel to prefill all the pipes and valves connected along the line so that sudden descaling high pressure would not burst the air along the pipe. No pressure based density variation was employed in this study. The wall shear stress computed using ANSYS Fluent code was found to be max where the actual failure had occurred. It has been noted that no pressure based density variation was employed in this study.