환기분사장치 분사가스의 압력 변화에 따른 초공동 유동 특성에 관한 연구

Cavity is generated by the fluid machine moves very high speed in the underwater, such as propellers, pump impellers, nozzles, injectors, torpedoes. And there are two main ways to generating cavitation. Natural cavitation is a phenomenon using a very high speed of the machine. It creates a bubble of gas to cover an object travelling underwater and it reduces the skin friction. It requires a very high speed while right after the launch of the underwater vehicle, such as a torpedo, proceeds at a very slow speed. So the ventilation devices add to make the cavity bubble cover the vehicle in the initial steps of launch. The ventilated cavity generation is related to the cavity pressure and the cavity pressure is related to the pressure of injected gas. This study shows the relationship between the pressure of ventilated gas and the flow characteristics. The cavity pressure is increased and the ventilated cavitation number is decreased as the pressure of the injected gas is increased.