STRESS POINTS FOR TENSION INSTABILITY IN SPH

In this work, the stress-point approach, which was developed to addres s tension instability and improve accuracy in Smoothed Particle Hydrod ynamics (SPH) methods, is further extended and applied for one-dimensi onal (1-D) problems. Details of the implementation of the stress-point method are also given. A stability analysis reveals a reduction in th e critical time step by a factor of 1/root 2 when the stress points ar e located at the extremes of the SPH particle. An elementary damage la w is also introduced into the 1-D formulation. Application to a 1-D im pact problem indicates far less oscillation in the pressure at the int erface for coarse meshes than with the standard SPH formulation. Damag e predictions and backface velocity histories for a bar appear to be q uite reasonable as well. In general, applications to elastic and inela stic 1-D problems are very encouraging. The stress-point approach prod uces stable and accurate results. (C) 1997 by John Wiley & Sons, Ltd.