| When the underwater vehicle is sailing at high speed in the water,the supercavitation technology can make the surface of the vehicle in the air except for the cavitator,which greatly reduces the resistance of the vehicle.When the supercavity cannot be formed when the vehicle is sailing,the air is introduced through the head to form a ventilated supercavitation to achieve drag reduction.The power unit of the underwater vehicle is generally installed in the tail,and the high temperature and high-pressure compressible gas are ejected through the tail nozzle to promote the navigation of the vehicle.After the tail gas jet is ejected,it involves a complicated flow mechanism,and there is a ventilation jet with the head.The interaction.In this paper,the method of numerical simulation is adopted,and the Mixture multiphase flow model is coupled with the Singhal et al.cavitation model to simulate and calculate the external flow field of the underwater vehicle at high speed in the water.The gas and cavitation under different influence factors are discussed.interaction between.The analysis of the calculation results shows that head ventilation can effectively increase the size of the cavitation bubble,and the cavitation size and the resistance of the navigation body show a trend of first slowly increasing and then rapidly increasing with the head ventilation flow;The size of the cavity has no obvious effect and can be ignored;the best gas for head ventilation is high-temperature compressible gas.The tail gas jet will reduce the size of the cavitation bubble and increase the resistance of the vehicle.The total temperature of the tail gas has little effect on the size of the cavitation and the resistance of the body;the increase of the total pressure of the tail gas causes the size of the cavitation and the resistance of the body to increase;the speed and water depth mainly change the size of the cavitation,and the increase in the speed causes the flow The increase in pressure increases the resistance of the vehicle.The increase in the size of the cavitation can increase the expansion area of the tail gas jet.As the gas jet is still under-expanded at the nozzle outlet in this article,the size of the cavitation affects the thrust of the vehicle.no effect.Head ventilation increases the internal pressure of the cavity and reduces the Prandtl-Meier angle of the expansion wave in the tail gas jet.The tail gas jet reduces the size of the cavity,which in turn reduces the expansion of the tail gas jet.Area,from which the available gas and cavitation interact and interact with each other. |
