In an LS-DYNA analysis, if any bodies have a reference frame set to S-ALE Domain, an S-ALE domain is created. The S-ALE domain is a structured hexahedral mesh.
Bodies with a reference frame set to S-ALE Fill are used to initialize material into the S-ALE domain. After the initialization of the solve, the mesh associated with such bodies is discarded. The surfaces of the S-ALE bodies are not tracked exactly - the location of materials in the S-ALE domain is stored as a material (volume) fraction for each of the S-ALE cells. A representation of the material surface can be displayed as an isosurface for a material fraction value of 50%.
A comparison of Lagrangian (left) and S-ALE (right) representations of the same body is shown below.
Results cannot therefore be displayed on the original mesh applied to the S-ALE bodies. Instead, a mesh is reconstructed for each material associated with the original body to which the result object is scoped. The reconstruction of the mesh is approximate and includes:
Finding the exterior surface of each material in its current location in the S-ALE domain. This is achieved by forming an isosurface on the volume fraction of each material in a cell (at 50%).
Filling the interior of the material with cells from the S-ALE domain that are completely inside the material.
Reconstructing an unstructured mesh for any gaps between the exterior surface and interior cells.
The example below illustrates a typical mesh displayed for a Results object scoped to a Body with S-ALE reference frame:
When the Show Undeformed Wireframe option is selected for a results object scoped to S-ALE bodies, the wireframe of the background S-ALE domain is displayed. Only the S-ALE domain cells that contain material at a given point in time are used to construct the wireframe (cells that only contain void are not displayed). An example is given below:
Results may be scoped to S-ALE bodies in the same way as for Lagrangian bodies.
Additional considerations:
Probes and path plots are not supported for S-ALE bodies.
External Force and Contact Force trackers will return zero for S-ALE bodies.
Deformation scaling (that is - Undeformed, .5 Auto, AutoScaling, 2x Auto, 5x Auto ) is not available for S-ALE bodies.
Show undeformed model is not available for S-ALE bodies.