A coupled Eulerian/Lagrangian method is presented to reduce the numerical diffusion observed in solutions of three-dimensional vortical flows using Eulerian finite volume time-marching schemes. A Lagrangian particle tracking method, added to the Eulerian scheme, provides a correction of the Eulerian solution. In turn, the Eulerian solution is used to integrate the Lagrangian state vector along the particles trajectories. While the Eulerian solution insures the mass conservation and sets the pressure field, the particles describe accurately the convection properties and enhance the vorticity and entropy capturing capabilities of the Eulerian solver. The Eulerian/Lagrangian coupling strategies are discussed and the combined scheme is tested on a constant stagnation pressure flow in a 90-deg bend and on a swirling flow in a pipe. As the numerical diffusion is reduced with the Lagrangian correction, a vorticity gradient augmentation is identified as a problem linked to the inviscid representation. The addition of a Lagrangian pseudodiffusion term to the combined scheme reveals a solution to the problem. The resulting solution still shows much lower diffusion than the basic Eulerian one. The reduction of numerical diffusion is quantified by comparing the combined scheme solutions with finer grid Eulerian results.
Eulerian/Lagrangian coupling procedure for three-dimensional vortical flows
Gekoppeltes Euler-Lagrangesches Verfahren für dreidimensionale Wirbelströmungen
AIAA Journal ; 33 , 1 ; 48-55
1995
8 Seiten, 14 Bilder, 16 Quellen
Article (Journal)
English
Eulerian-Lagrangian Coupling Procedure for Three-Dimensional Vortical Flows
Online Contents | 1995
|An Eulerian/Lagrangian Coupling Procedure for Three-Dimensional Vortical Flows
British Library Conference Proceedings | 1993
|British Library Conference Proceedings | 1993
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