Results of von Neumann analyses for reproducing kernel semi-discretizations

摘要

The Reproducing Kernel Particle Method (RKPM) has many attractive properties that make it ideal for treating a broad class of physical problems. RKPM may be implemented in a mesh-full or a mesh-free manner and provides the ability to tune the method, via the selection of a dilation parameter and window function, in order to achieve the requisite numerical performance. RKPM also provides a framework for performing hierarchical computations making it an ideal candidate for simulating multi-scale problems. In order to assess the numerical performance of RKPM, detailed studies of RKPM on a series of model partial differential equations has been undertaken. The results of von Neumann analyses for RKPM semi-discretizations of one and two-dimensional, first and second-order wave equations are presented in the form of phase and group errors. Excellent dispersion characteristics are found for the consistent mass matrix with the proper choice of dilation parameter. In contrast, the influence of row-sum lumping the mass matrix is shown to introduce severe lagging phase errors. A higher-order mass matrix improves the dispersion characteristics relative to the lumped mass matrix but delivers severe lagging phase errors relative to the fully integrated, consistent mass matrix.