The Study Of Cavitation Gain And Its Applications On Supercavitation Weapons

The cavitation layer of the Underwater supercavitation weapons make it bearing a lower resistance of 1-2 magnitude normally than the liquid resistance of entire circular current movement object beared, hense the speed of the underwater movement object will be improved up to ten times, and the strick capability will be enhanced greatly.Cavitation is a cavity phenomenon that water current or liquid current occurred suddenly under low pressure location. Cavitation inception not only related to liquid vaporization pressure, but also relevant to the gas core quality and quantity in liquid directly. Both the micro air core and solid micro inclusion in water are air core for cavitation generate, micro air bubble is the main element of air core in river water or seawater. Based on the theories that movement cavity air bubble is generated by air core micro air bubble, the size and quantity of the air core has a big relation to the cavitation occurrence rate, this will greatly influence the quantity of inception cacitaton consequently.The key point of this paper is to propose the follow items by analysis:1. By manual injected air core to change the quantity in water, add an air core generate system at the front side of the cavitator. The concentration of the micro air core in the water at the front side path of the cavitator will be increased, which will increase inception cavitation quantity of the cavitator, and benefit cavity achievement.2. When analysis the relation of air core size and quantity to the cavitation inception, there need pay more attention to the Screening Effects the big bubble to the object surface.3. The method decreasing the Screening Effects of object surface to the big bubble is: deep analyse the cavitation bubble's generate and collapse near object surface with cavity bubble dynamics, big bubble will convert to small bubble during the collapse procedure near the object surface, the same bubble will rebound after collapse under certain condition, then collapse again. After collide rupture with the cavitator fixed surface, big bubble will fragmentate to small air core, thus will increase the air core concentration in a unit liquid, the change of the concentration will greatly effect cavitation.4. At the end of this paper, the author proposed a method on how to reduce the energy loss of the cavitator:lead in vortex cavitation theoty to get a conclusion that the usage of the vortex cavitation on supercavitation system can decrease the energy loss of the high speed objects.The research result of this project will improve the movement capability of the underwater weapons, increase the penetration strike capability, improve endurance capability of navigate object.