Dynamic fracture simulation of flexible multibody systems via coupled finite elements of ANCF and particles of SPH

A parallel computation methodology is proposed to study the dynamic fracture process of a flexible multibody system with initial cracks. The potential fracture domains of the flexible body system are described by using the particles of smoothed particle hydrodynamics (SPH), and the other domains of the system are modeled by using the finite elements of absolute nodal coordinate formulation (ANCF). In order to preserve the continuity of deformation field, extra virtual particles are uniformly embedded into the interface, where the finite elements of ANCF and the particles of SPH are connected, so as to transmit the interaction forces. The OpenACC derivatives are used to parallelize both the particle contact detection and the solution of the integral equations. A predictor-corrector scheme is used to solve the ordinary differential equations for the particles of SPH, while the generalized-alpha method is used to solve the huge set of differential algebraic equations for the multibody system. The OpenMP derivatives are also used to parallelize the evaluation of the elastic force vectors and their Jacobi matrices of the finite elements. Finally, three case studies are given to validate the proposed computation methodology.