Altair ultraFluidX 2022.3 Release Notes

New Features

Command-line based ultraFluidX post processing tool
There is a new command-line based post-processing tool to analyze EnSight results and aerodynamic coefficients from previous ultraFluidX simulations. You can compute minimum, maximum, arithmetic mean, and standard deviation of field variables and aerodynamic coefficients. These values can be computed in a user-defined time interval and for each element in the input data set. Reduction operations, such as the computation of global minimum or maximum, are not supported yet. The tool can process merged and distributed EnSight files and does not require GPUs.

Enhancements

Memory balance for multi-GPU overset mesh simulations
This release introduces an improved domain decomposition algorithm that reduces the memory imbalance for overset mesh simulations running on multiple GPUs. The GPU memory allocation is more evenly distributed across multiple GPUs, which enables larger simulations.
More efficient output of overset mesh regions
There is now an option to deactivate the time-varying EnSight .geo output to reduce the memory footprint and the number of files on disk. Additionally, you can turn off the time-varying geometry output to improve performance for section cut and partial volume outputs that are intersecting with overset mesh regions. In this case, the output topology is not updated at runtime anymore, and the initial mesh topology of the section cut or partial volume is used for all subsequent outputs.
Moreover, as an alternative to the full time-varying EnSight .geo output, there is an additional field variable (mesh_displacement) that includes information on the displacement of each cell in the computational mesh. This reduces the memory footprint on disk compared to the full EnSight .geo output.
Time-varying Geometry Output Mesh Displacement Comments
True (Default) False (Default) EnSight .geo files are written at each recording time step (this is the behavior from the previous release).
False False EnSight .geo file is written only once. This option has the smallest footprint on disk, but without the ability to reconstruct the rotation of the OSM.
False True EnSight .geo file is written only once. An additional field variable is written to eventually enable the reconstruction of the OSM displacement.

Resolved Issues

  • The outlet pressure boundary condition has been improved to address vehicle aerodynamics cases with explicit ground plates intersecting with the outlet plane and cases with zero reference velocity.