基于ISPH-TLSPH的充液多柔体动力学建模与计算

Based on the incompressible smoothed particle hydrodynamics (ISPH) and total Lagrange smoothed particle hydrodynamics (TLSPH) method, a numerical computation methodology is proposed for simulating the dynamics of fluid-filled flexible multibody systems. Compared with the conventional SPH method, a larger time step can be used in the iteration procedure, the obtained pressure fields are free from spurious oscillations, and the tensile instability problem in simulation of the flexible bodies can also be alleviated. With the particle shifting technology, the smooth pressure field of the fluid can be obtained by solving the hybrid pressure poisson equation. An artificial viscosity term is introduced to maintain the numerical stability of the TLSPH. On the fluid domain, the solid particles are treated as dummy particles to solve the pressure poisson equation in the ISPH. On the solid domain, the interaction forces between fluid particles and solid particles are applied in the momentum equation as external forces within the TLSPH solver. Finally, the effectiveness of the ISPH, TLSPH and ISPH-TLSPH coupling method is validated by five numerical examples and experiment, and then the proposed method is applied to simulate the dynamics of fluid-filled flexible multibody system.