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DOE OSTI · 1304832

A 3D finite element ALE method using an approximate Riemann solution

Chiravalle, V. P.·Morgan, N. R.
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Abstract

Arbitrary Lagrangian–Eulerian finite volume methods that solve a multidimensional Riemann-like problem at the cell center in a staggered grid hydrodynamic (SGH) arrangement have been proposed. This research proposes a new 3D finite element arbitrary Lagrangian–Eulerian SGH method that incorporates a multidimensional Riemann-like problem. Here, two different Riemann jump relations are investigated. A new limiting method that greatly improves the accuracy of the SGH method on isentropic flows is investigated. A remap method that improves upon a well-known mesh relaxation and remapping technique in order to ensure total energy conservation during the remap is also presented. Numerical details and test problem results are presented.

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BibTeXRIS

Chiravalle, V. P., Morgan, N. R.. 2016-08-09. A 3D finite element ALE method using an approximate Riemann solution. https://doi.org/10.1002/fld.4284

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