Abstract
In the present study, the optimal shape of a spool valve was determined to reduce axial flow forces by solving the inverse problem. The basic assumptions in the present calculation are that the axisymmetric flow is incompressible, steady and inviscid. The basic equations were led by taking the stream function and the velocity potential as independent variables, and the equations were solved by the relaxation method. Next, the steady axial flow forces on spools of a conventional valve and the valve calculated by the present method were measured with a load cell. Furthermore, the unsteady axial flow forces for sudden valve opening were also measured and the effect of the spool valve obtained by the present method on reducing the axial flow force was investigated.
