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Comments on the diffusive behavior of two upwind schemes
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Kleb, William L. Wood, William A. |
| Copyright Year | 1998 |
| Description | The diffusive characteristics of two upwind schemes, multi-dimensional fluctuation splitting and locally one-dimensional finite volume, are compared for scalar advection-diffusion problems. Algorithms for the two schemes are developed for node-based data representation on median-dual meshes associated with unstructured triangulations in two spatial dimensions. Four model equations are considered: linear advection, non-linear advection, diffusion, and advection-diffusion. Modular coding is employed to isolate the effects of the two approaches for upwind flux evaluation, allowing for head-to-head accuracy and efficiency comparisons. Both the stability of compressive limiters and the amount of artificial diffusion generated by the schemes is found to be grid-orientation dependent, with the fluctuation splitting scheme producing less artificial diffusion than the finite volume scheme. Convergence rates are compared for the combined advection-diffusion problem, with a speedup of 2.5 seen for fluctuation splitting versus finite volume when solved on the same mesh. However, accurate solutions to problems with small diffusion coefficients can be achieved on coarser meshes using fluctuation splitting rather than finite volume, so that when comparing convergence rates to reach a given accuracy, fluctuation splitting shows a speedup of 29 over finite volume. |
| File Size | 1338621 |
| Page Count | 52 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19990009124 |
| Archival Resource Key | ark:/13960/t7zm08t53 |
| Language | English |
| Publisher Date | 1998-10-01 |
| Access Restriction | Open |
| Subject Keyword | Numerical Analysis Triangulation Stability Algorithms Computational Fluid Dynamics Upwind Schemes Mathematics Finite Volume Method Nonlinearity Scalars Diffusion Coefficient Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
