1967 年 29 巻 3 号 p. 132-136
The static characteristics of flat, conical and ball valves which supplied the effective head varied in 6 stages from 40cm to 140cm, were described in this report.
The discharge Q was measured at each valve lift h under a constant effective head H.
From these experimental data, thus nondimensional discharge q0, coefficient of discharge C and coefficient of resistance ζ0 were computed and expressed as functions of opening ratio h/d0. (d0: valve-port diameter)
The following results were obtained.
1) The discharge Q increased with the increase of effective head H.
2) The non-dimensional discharge q0 increased with the increase of opening ratio h/d0.
3) The coefficient of discharge C was the maximum valve in the range of opening ratio h/d0=0.02-0.035, but not exist the maximum valve in the ball valve.
4) On the coefficient of resistance ζ, the ball valve was found the influence of valve-port diameter.