High Performance Balanced Flow Modulating Hydraulic Control Valves

Abstract

Inertia, strength, actuator capabilities and flow gain represent major concerns in valve design. In this paper, balanced rotary plate valves are introduced, aiming at maximizing flow gain and strength, and minimizing inertia for high valve dynamic performance. A newly developed electromagnetic actuator capable of driving the valve is presented. A valve of this type incorporates a limited angle rotating plate (rotor) inserted between two stators, such that control orifices of considerable large areas result from small input angular displacements, and thus a high flow gain is realized. The rotor is designed to be highly balanced regarding the axial pressure and flow forces. A rotor of thin sections and low inertia would consequently have enough strength to withstand the loads. The geometrical features of the rotor and the stator plates are determined such that the walls separating the various chambers undergo similar deformations with small relative location changes to keep control orifices unchanged as they are subjected to similar pressure differences. Control orifice pairs exist at both sides of the rotor plate and thus the control areas are duplicated. A proposed mechanical design for a valve size NG 6 is presented and the stresses and deformations in its main parts are determined and verified to be safe using ANSYS Mechanical software package. Computational fluid dynamics analysis of the flow pattern is performed using ANSYS/FLUENT. The analysis results show that the proposed valve design well suits building single stage valves of high flow capacity and high dynamic performance.