ダクト付きボール弁のボールの挙動と流れ
1983 年 12 巻 1 号 p. 150-153
詳細
1983 年 12 巻 1 号 p. 150-153
A ducted ball valve is newly designed for an extracorporeal assist device. A ball is set up in a well-contoured duct along which the flow velocity is to be constant. This vale wastested and compared with a Bjork-Shiely valve and a St. Jude Medical valve in a steady flow and in a pulse duplicator. This valve proved almost the same pressure-loss as a SJM valve, the lowest in regurgitation, and the minimum in energy-loss.
Simultaneous measurements of ball displacement, flow rate and pressure-loss indicate that (1) the ball valve begins to close before regurgitation, this results in lowest regurgitation, (2) at the initial stage of valve-opening, the ball moves faster than the fluid, (3) at the end of opening or closing period, the ball touchs the cage or the valve seat at the much-reduced speed.
