Optimal Orifice Geometry for a Hydraulic Pressure-Reducing Valve

In this paper, the flow gain of a hydraulic pressure-reducing valve is examined. It is noted that classical linear-analysis is typically used to optimize the flow gain of hydraulic control-systems and that in practice this parameter is usually nonlinear. For this reason, it is important that a designer know how to reconcile the optimization using linear analysis with the implementation of the nonlinear physical design. In particular, this paper concerns itself with the steady-state flow gain and the shape of the flow passage that contributes to the nonlinear flow-gain characteristics. The shapes of a circle, a rectangle, a diamond, and a triangle are discussed and it is shown that a triangular shape provides an optimal flow passage compared to other shapes of similar size.