ALE and FSI

In this seminar, you receive comprehensive information directly from one of the program developers about the latest developments of the features provided by the solver LS-DYNA to analyse fluids and, in particular, the fluid-structure interaction using its Arbitrary Lagrangean Eulerian (ALE) capabilities.

The theoretical background to fluid modeling in LS-DYNA is presented and illustrated with several practical applications. Problems solved during the workshop include tank sloshing, tank dropping (partially and completely filled), viscous flow in a channel, underwater explosion, bird strike, ship collision and acoustics in air and water.

The seminar is directed towards advanced LS-DYNA users, whereas prior knowledge of fluid dynamics is not required.

Contents

• Lagrangean formulation (relevant mathematical equations, discretization and numerical solution)
• Eulerian formulation of one material (relevant mathematical equations, operator-split technique, advection ratio)
• ALE formulation of one material (algorithm for mesh smoothing)
• Eulerian formulation of several materials (tensions weighted according to volume fractions, transition reconstruction)
• ALE formulation of several materials (functioning of a moving Eulerian mesh)
• Fluid-structure interaction (method with constraints), penalty-based method, problem of leakage and solution to it
• Examples of application