自转平板匀速入水空泡演变的数值模拟研究

Numerical simulation study on cavitations evolution of rotating plate with uniform velocity into water

研究了运动平板在入水过程中形成空泡和空泡的形状、大小对平板的运动状态以及水的运动行为的影响。采用体积分数方法空化模型和动网格技术研究平板入水过程,利用商业流体力学计算软件Fluent,添加自行编制的程序对平板速度进行编译。研究结果表明:自转平板匀速入水过程中空泡的形态随流体运动轨迹变化过程从敞开、闭合到溃灭;由于排液作用,在平板两侧出现漩涡,随后漩涡逐渐汇合,而液相阻力随时间先增大后减小,然后趋于稳定。

In this paper,the object is moving plate entering water.The rotating plate into the water belongs to the rigid body into the water,in the process,the cavitations form.The shape and size of cavitation will influence the motion behaviors of plate and water.In present study,Volume of Fluid(VOF)cavitation model is used to predict the process of the plate entering the water,and k-εmodel is adopted to simulate the liquid phase turbulence.A dynamic grid technique is applied to model the motion process of the plate in water,and its relevant code is compiled by UDFs with Fluent 17.Simulation results indicate that the evolution of cavitation experiences opening,closing and to collapsing during the process of the rotating plate with uniform velocity into water.In return,the trajectory of water is changed,namely,the whirlpools appear on both side of plate due to water discharging,and then the whirlpools gradually converge.Meanwhile,the liquid resistance increases first and then decreases and tends to be stable finally with time.