Mathematical Model of Spool Valve with Rectangular Grooves

A spool valve of aerospace hydraulic breaks down because of uneven pressure distribution between sleeve and spool, which is called as hydraulic lock. The rectangular grooves on the spool surface can effectively weaken the lateral force, thereby preventing the hydraulic lock. So the mathematical model of spool valve with rectangular grooves is established according to the Navier-Stokes equations based on the cylindrical coordinate system. To verify the effectivity of the mathematical model, the numerical simulation is compared and used to modified the mathematical model.