A generalized simple implicit interpolation scheme in CFD for non-conforming meshes

摘要

The non-conforming meshes are widely used in numerical simulations to solve complex flow problems and the key is to perform accurate and efficient interpolation between subdomains. This paper presents a generalized and simple implicit interpolation scheme at algebraic level for the coupling of non-conforming meshes in computational fluid dynamics (CFD). The final equations for most of numerical methods are always of an algebraic form and that is where the interpolation process is conducted. The substitution of dependent nodes with a linear combination of those in neighboring subdomains is imposed in algebraic equations to ensure continuity of variables. A simple reconstruction of the system matrix and right hand side is then executed which implements the reaction of the variable constraint of dependent nodes on replacing ones and maintains the properties of algebraic system. In other words, the proposed interpolation scheme can be regarded as a Dirichlet/Neumann condition performed on algebraic system implicitly. Compared with existing interpolation methods for non-conforming meshes, the new method escapes from the restraints of the type of problem, the form of grids, the discretization scheme and the solver. It also has advantages in simplicity and efficiency. Several benchmark problems were carried out to illustrate the accuracy of the proposed method. (C) 2019 Elsevier Ltd. All rights reserved.