Stationary Axial Flow Forces Analysis on Compensated Spool Valves

The paper deals with the application of a simplified numerical analysis, based on Computational Fluid Dynamics (CFD), of the flow field inside the compensated port connections of a reference spool valve. The aim of the study was the evaluation of the proposed analysis procedure, to put in evidence the major effects related to the presence of steady state flow forces affecting the spool equilibrium. Starting from an initial summary of the dimensional analysis proposed by the authors to approach the application of CFD to hydraulic components, the paper presents the results of three commonly used compensating profiles for two reference spool positions. In order to validate the simulation, the curves obtained for one of the three geometries are compared with the experimental data obtained on an equivalent port connection of a commercial distributor.