Altair nanoFluidX 2025 Release Notes

• Up to 1.2x performance improvement in Tartakovsky F1 surface tension model.

Optional reference velocity in body frame

Specifying reference velocity is now optional when body frame is active. This simplifies case setup where high acceleration events are more dominant than high speed events, for example in predominantly vibrational tank sloshing cases.

Independent interpolation domain size in nFX[c]

Interpolation domain size of nFX[c] can now be set independently from nanoFluidX. This simplifies narrowing down the post-processing data to the volume of interest.

Performance improvement in Tartakovsky F1 surface tension model

Tartakovsky F1 surface tension model implementation has been modified, offering up to 1.2x speedup compared to prior implementation.

Load balancing adjustment for cases with large wetting area

Load balancing method in Weighted interaction scheme has been adjusted to account for cases with larger wetted surface to fluid bulk ratio, offering performance improvements for some water management and water wading cases.

Memory usage summary

In addition to the running memory usage, a summary of peak memory usage of host and device can now be shown at the end of the simulation log. The summary is activated via specifying relevant options in the configuration file.

Availability of cell mesh information prior to simulation

Domain addressing and cell mesh data can now be viewed when running nFX[p], nFX[c] in --nfxp mode or Data Check in SimLab.

• Total number of interpolation points exceeding 2147483647 led to unexpected behavior in nFX[c].