Coupling Smoothed Particles Hydrodynamics And Smoothed Point Interpolation Method For Sloshing Problems

Sloshing in a tank is a classic problem in ship and ocean engineering.Due to its strong nonlinear characteristics,there are many difficulties in numerical simulation.Sometimes,the sloshing involves fluid-structure interaction(FSI).For example,baffles are usually installed in the tank to suppress sloshing.At this time,it is necessary to consider both the free surface of the fluid and the deformation of the solid.In this paper,the smoothed particle hydrodynamic and smoothed point interpolation coupled method(SPH-SPIM coupled method)and the improved ? smoothed particles hydrodynamics and smoothed point interpolation coupled method(?SPH-SPIM coupled method)are used for numerical simulation of the sloshing problem involving FSI.It is verified that these two methods can be well applied to the above problems.In this paper,the smoothed particle hydrodynamic(SPH)method is used to simulate the fluid in the tank.As a meshless particle method,SPH has unique advantages in simulating strong nonlinear free surface problems,which is very suitable for simulating the large deformation of the free surface.This paper verifies this conclusion through a violent sloshing problem.The smoothed point interpolation method(SPIM)is used to simulate the solid.The SPIM combines the advantages of the traditional finite element method and the meshless method.By using the G-space theory and weakened weak forms,the model stiffness of the solid is softened,which is good in simulating large solid deformation problems.The SPH-SPIM coupled method is achieved by coupling SPH with SPIM,and the effectiveness of the proposed method is verified from three aspects of accuracy,convergence and energy conservation.Subsequently,the SPH-SPIM coupled method is employed in simulating the sloshing problem involving FSI.Based on the SPH-SPIM coupled method,the ?SPH and a new FSI force transmission method is employed for improvement.For the pressure oscillation of weakly compressible SPH(WCSPH),referring to the work of other scholars,?SPH is used in the program.?SPH improves the pressure distribution by adding the density diffusion term to the continuity equation to improve the particle distribution during simulation.In this paper,the case of still water in a tank shows that ?SPH can indeed reduce the pressure oscillation.A new transmission method for FSI force called the real fluid particles calculation is proposed.The mainly difference between this method and the previous method is that no ghost particles or repulsive particles are used during the FSI force calculation.Thus only real fluid particles are used.In this paper,through the example of high speed impact of an elastic wedge,the numerical simulation by using the real fluid particles calculation and the one-to-one transition are compared,indicating the advantages of the former method.Finally,the ?SPH-SPIM coupled method is applied to the dam break flows and the sloshing involving FSI,which verifies the good performance of the present method for solving FSI problems.