
Positive Definite Advection Transport Algorithm for Conservation Law Equations on Nonuniform Irregular Grids
Author(s) -
Xigang Yuan,
Chunguang Xiong
Publication year - 2020
Publication title -
mathematical problems in engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.262
H-Index - 62
eISSN - 1026-7077
pISSN - 1024-123X
DOI - 10.1155/2020/5283139
Subject(s) - discretization , positive definite matrix , polygon mesh , grid , advection , upwind scheme , computation , mathematics , finite volume method , taylor series , boundary (topology) , conservation law , numerical analysis , algorithm , mathematical analysis , geometry , mechanics , physics , eigenvalues and eigenvectors , quantum mechanics , thermodynamics
The multidimensional positive definite advection transport algorithm (MPDATA) is an important numerical method for the computation of atmospheric dynamics. MPDATA is second-order accurate, positive definite, conservative, and computationally efficient. However, the method is problematic in which it results in a loss of precision when computing a nonuniform irregular grid. Furthermore, research revealed two reasons for this problem. On the one hand, numerical discretization of boundary derivatives of the finite-volume method is incompatible with nonuniform meshes (or grids); on the other hand, the up-wind scheme of staggered grids is not applicable to the calculation of irregular grids. We overcome these two problems by using the multipoint Taylor expansion method to obtain a boundary derivative numerical approximation scheme that does not depend on the grid structure. Furthermore, combined with the well-balance central-upwind scheme, a positive definite advection scheme for irregular meshes is proposed. Then, the positivity of the new numerical scheme is analyzed. Finally, the result of this study is verified by numerical simulation.