Mathematical base of Difference Operator of Particle Method

Abstract: Mathematical base of difference operators in Moving Particle Semi-implicit method (MPS) are not given sufficiently in contrast to Smooth Particle Hydrodynamics method (SPH). Iribe and Nakaza proposed a method to improve the accuracy of the gradient operator, and Khayyer and Gotoh gave an ingenuity also for gradient operator too. An extension to higher order difference operators of Iribe-Nakaza method is given in this paper. The proposed method is a special case of the author's method called Discrete Differential Operators on Irregular Nodes (DDIN).