A contact algorithm for smoothed particle hydrodynamics

This paper describes the development and testing of a contact algorithm for Smoothed Particle Hydrodynamics (SPH). The treatment of contact boundary conditions in SPH has not been adequately addressed, and the development of the normalised smoothing function approach has highlighted the need for correct treatment of boundary conditions. A particle to particle contact algorithm was developed for 2D. The penalty formulation was used to enforce the contact condition, and several equations for the penalty force calculation were considered. The contact algorithm was tested for 1- and 2D problems for the velocity range between 0.2 and 4.0 km/s to determine the best penalty force equation and the best approach for applying the contact force. The tests showed that the zero-energy mode problem in the SPH method had to be addressed, as contact excited a zero-energy mode that caused non-physical motion of particles. The test results were compared to the DYNA3D results for the same problems. (C) 2000 Elsevier Science S.A. All rights reserved.