Abstract
In recent years, importance of hydraulic power generation is further increasing because of decarbonization and its availability of flood prevention in Japan. For this reason, demand for dam discharge valves has been increasing. There still remains problems to improve reliability of the valve systems due to complicated two-phase flows take place in the valve. Therefore, in this study, we attempt to apply a link-sleeve valve (LSV), which is usually used for public water supply, as a dam discharge valve. In general, to prevent cavitation erosion, vibration, and noise, air is injected into the downstream pipe of dam discharge systems. Since the LSV is designed to operate in a pressured water supply system, however, characteristics of the air-water two-phase flows in LSV have not been investigated. In order to clarify the characteristics of the air entrainment by water jets in the LSV, experiments were conducted. As a result, it was found that there was similar analogy with a jet pump at high water flow rate, while air suction characteristics shows complicated characteristics at low water flow rates.
