Agglomeration Multigrid Solutions of Laminar Viscous Flows

On the Development of an Agglomeration Multigrid Solver for Turbulent Flows

The paper describes the implementation details and validation results for an agglomeration multigrid procedure developed in the context of hybrid, unstructured grid solutions of aerodynamic flows. The governing equations are discretized using an unstructured grid finite volume method, which is capable of handling hybrid unstructured grids. A centered scheme as well as a second order version of ...

An Agglomerated Multigrid Method on Unstructured Hybrid Grids for Turbulent Compressible Flow

A multigrid accelerated Navier–Stokes solver, utilizing mesh agglomeration on hybrid meshes is described. The governing equations are discretized by a finite volume approach where stabilisation and discontinuity capturing is achieved by the use of a JST flux function on each edge. The method is an attempt to reduce computational cost of viscous calculations on unstructured meshes and some examp...

Directional Agglomeration Multigrid Techniques for High-Reynolds Number Viscous Flows

A preconditioned directional-implicit agglomeration algorithm is developed for solving twoand three-dimensional viscous flows on highly anisotropic unstructured meshes of mixed-element types. The multigrid smoother consists of a pre-conditioned pointor line-implicit solver which operates on lines constructed in the unstructured mesh using a weighted graph algorithm. Directional coarsening or ag...

Towards Problem-independent Multigrid Convergence Rates for Unstructured Mesh Methods I: Inviscid and Laminar Viscous Flows

Agglomeration Multigrid for Viscous Turbulent Flows

Agglomeration multigrid, which has been demonstrated as an efficient and automatic technique for the solution of the Euler equations on unstructured meshes, is extended to viscous turbulent flows. For diffusion terms, coarse grid discretizations are not possible, and more accurate grid transfer operators are required as well. A Galerkin coarse grid operator construction and an implicit prolonga...