Static Characteristics of the Orifices in a Pilot Operated Pressure Relief Valve

In this paper the static characteristics of the sharp edged orifices have been investigated. Mathematical relationship between pressure loss and flow through the orifice has been developed and solved for orifices mainly used in pilot operated pressure relief valves. A CFD simulation of the flowing process has been done. A full CAD model of the volume for orifices with different geometric parameters was created and meshed at finite number of elements. As a result of the CFD computations, few diagrams have been presented and compared to the theoretical ones. The discharge coefficient and the pressure loss coefficient have been obtained.