Finite-Sized Fluid Particle in a Nonuniform Moving Grid

A PIC method of a new type is developed and shown to be useful for the description of large density variation with few particles. Nonphysical noise, numerical thermal diffusion, and viscosity are successfully reduced. A nonuniformly spaced moving grid system can be used for locally fine resolution of processes. The detailed description of the scheme and its application to real situations will appear in a forthcoming paper, where the extension to a polar coordinate system will also be discussed.