Entrained air amount measurement through an open channel

Air can be absorbed into a pump if the flow in the pump suction becomes turbulent, which results in vibration, cavitation and low efficiency in the pump. The experiment on entrained air amount measurement has been carried out by using the capacitance air void meter which was manufactured by authors. The experiments results show that the entrained air amount increases if the flow velocity or the water depth increases, and that the entrained air amount is smallest relatively when the angle of the anti-vortex wall equals d = 30°C. The flow can become smooth and entrained air amount can decrease, if the angle of the anti-vortex wall is selected appropriately.