Determination of the Effective Quantities in Flow Linearized Equation for Hydraulic Directional Control Valves

In this paper, the discharge coefficient and the flow linearized coefficients for hydraulic valves with spool are examined. The discharge coefficient was determined for orifice created by spool in turbulent flow and the linear part slope of C Re d - curve, 0.6229 and 0.222, respectively. Furthermore, the variation range of pressure-flow coefficient for valves with zero overlap is less than valves with negative overlap. On the other hand, the flow gain for valves with zero overlap has more changes than valves with negative overlap.