Studies on the Pumping Performance of Power Sprayer (II)

Static Characteristics of Valve in High Pressure

Abstract

The static characteristics of valves which supplied the pressure head varied from 0.1 to 15kg/cm², were described in this report. The same valves which used in previous report were used.
The discharge Q and lifting force P were measured at the various valve lift h under the various pressure head H.
From these experimental data, the non-dimensional discharge q₀, coefficient of discharge C, coefficient of resistance ζ which used in previous report and non-dimensional lifting force P₀ were computed and expressed as functions of opening ratio h/d₀., (d₀: valve-port diameter)
The following results were obtained.
1) The non-dimensional discharge q₀ increased linearly with the increase of opening ratio h/d₀ in all valves.
2) The coefficient of discharge C was the maximum value in the range of opening ratio h/d₀=0.02-0.03, but not the maximum value in the ball valve.
3) On the coefficient of resistance ζ, the ball valve was found the inflence of valve-port diameter.
4) The non-dimensinal lifting force P₀ was the minimum value at opening ratio h/d₀=0.04 in the flat valve, and was the minimum value in the range of opening ratio h/d₀=0.12-0.13 in the conical valve. On the ball valve, there was not the minimum value.