Abstract:

In view of the existing problem which does not accord with the fact, that is, in the hydraulic valve flow field CFD study, the single-phase flow model ignores the influence on fluid density and fluid flow field under the condition of cavitation occurred, which leads to the result of the lower relative pressure, by using Fluent software and multiphase model, field distribution is studied on the converged flow sliding valve, and the influence by the change in the flow rate and valve orifice is analyzed on the spool wall pressure distribution and the steady-state flow force. A measurement scheme of wall pressure distribution is designed. The surface integral of the measurement value is the steady flow force. The result is the experimental data is consistent with the simulation’s, and the peak of the wall pressure distribution decreases with the increasing of the orifice area. the orifice area is smaller, the direction of the steady flow force is the direction of the orifice closing. when the orifice area reaches a critical value, its direction is the direction of the orifice opening. the formula of the steady flow force on the slide valve omits the changes of the flow angle at the orifice and the momentum at the exit, so it makes the bigger error for the steady flow force, the direction of steady flow force always points to the direction of the valve orifice opening.

Key words: converged flow sliding valve, pressure distribution, steady axial flow force, two-phases flow