Modified Particle Method with integral Navier-Stokes formulation for incompressible flows

摘要

In this work, a modified Particle Method in fluid mechanics involving irregular distribution and discontinuity issues is proposed. Due to the approximation accuracy, momentum conservation and governing equation feasibility, traditional Particle Method, Moving Particle Semi-implicit (MPS) method in this paper, cannot guarantee the accuracy and stability of computation, and the divergence calculation in Navier-Stokes equation may cause numerical error in computation domain with discontinuity. To enhance the computation accuracy of Particle Method, we modify the gradient operator with a corrected tensor emanating from minimizing the local error of the first-order Taylor Expansion approximation. Besides, inspired by Peridynamic which is mostly used in solid mechanics, a new governing equation in an integral form which maintains the momentum conservation is obtained. Combining the modified gradient and new governing equation, we obtain a new particle-based method. The numerical results verify its feasibility and illustrate a good computational performance of proposed Method in the fluid dynamics involving non-uniform particle distribution. (C) 2018 Elsevier Inc. All rights reserved.