Reynolds number effects on the performance of safety valves operating with incompressible flows

The results obtained have shown that whilst the discharge coefficient decreases for increasing values of the fluid viscosity, the force acting on the valve disc may exhibit a non monotonic behavior. Variations in the force exerted by the flow affect the operating performance and lead in some cases to an additional reduction of the valve flowing capacity. The critical evaluation of the results allows to suggest a modification of the sizing procedure proposed by the reference standards.