The Discharge Coefficient of Spool Type Hydraulic Valve : 3rd Report, The Taper Land Spool Valve

抄録

In this report, the discharge property of a taper land spool valve is analyzed theoretically on the assumption of laminar flow and verified experimentally. Theoretically, we assume a taper land channel as a two-dimensional divergent or convergent channel, and obtain a pressure loss with approximate velocity profile. In the inlet part, we apply the similarity of velocity profile to a boundary layer equation and obtain a pressure loss in the inlet length. Experimentally, we make a model of two-ports valve and obtain precise data. Taper angle is set to be 1.5°∼6°, spool displacement 0.5∼4 mm, Reynolds number 10∼1, 200. In this range we experiment, and compute the discharge property in the same range. In the result, experiment data show good coincidence with computation result. Further, the influences of back pressure of the valve are also discussed.