Two compact higher-order methods are presented for solving the Euler equations in two dimensions. The flow domain is discretized by triangles. The methods use a characteristic-based approach with a cell-centered finite volume method. Polynomials of order 0 through 3 are used in each cell to represen
Effect of discretization order on preconditioning and convergence of a high-order unstructured Newton-GMRES solver for the Euler equations
โ Scribed by Amir Nejat; Carl Ollivier-Gooch
- Publisher
- Elsevier Science
- Year
- 2008
- Tongue
- English
- Weight
- 520 KB
- Volume
- 227
- Category
- Article
- ISSN
- 0021-9991
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โฆ Synopsis
This article studies the effect of discretization order on preconditioning and convergence of a high-order Newton-Krylov unstructured flow solver. The generalized minimal residual (GMRES) algorithm is used for inexactly solving the linear system arising from implicit time discretization of the governing equations. A first-order Jacobian is used as the preconditioning matrix. The complete lower-upper factorization (LU) and an incomplete lower-upper factorization (ILU(4)) techniques are employed for preconditioning of the resultant linear system. The solver performance and the conditioning of the preconditioned linear system have been compared in detail for second, third, and fourth-order accuracy. The conditioning and eigenvalue spectrum of the preconditioned system are examined to investigate the quality of preconditioning.
๐ SIMILAR VOLUMES
In this paper, for a Newton-like method for solving block nonlinear equations arising in the numerical solution of stiff ODEs y' = f(y), which involves a smaller quantity of computation, we prove that it is convergent and the convergence is independent of the stiffness of f(y), and give the error es