Altair nanoFluidX 2020.1 Release Notes

nanoFluidX is a software to simulate single- and multi-phase flows based on the Lagrangian Particle Method "Smoothed Particle Hydrodynamics" (SPH) and is developed and maintained by Altair Engineering.

The purpose of this code is to simulate complex flows that are difficult or infeasible to handle using classical CFD approaches, such as Finite Volume Methods. The main advantages of SPH are the conservation of mass and momentum (linear and angular) in the absence of physical dissipation e.g. due to viscous shear effects and the exact advection of the particles. As a consequence, SPH is very powerful in dealing with free-surface flows as well as multi-phase flows with complex physical phenomena such as surface-tension or interfacial transport processes.

Highlights

  • Introduction of nanoFluidX Prep tool – nFX[p] – for easier validation of the run setup. nFX[p] is effectively running a portion of the simulation initialization and it is independent of GPU presence. By running this partial initialization routine, numerous setup flaws can be detected before starting the full run.

New Features

  • Introduction of nanoFluidX Prep tool – nFX[p] – for easier validation of the run setup. nFX[p] is effectively running a portion of the simulation initialization and it is independent of GPU presence. By running this partial initialization routine, numerous setup flaws can be detected before starting the full run.
  • Auxiliary material for post-processing (ParaView) – nanoFluidX toolbox plugin and material library.
  • Reporting memory usage of the run in the log file.

Enhancements

  • Improve directory structure creation for multi-node runs (added option to override).
  • PASSIVE_RIGID_BODY motion is now responsive to variable acceleration.

Known Issues

  • Surface tension coefficient for single phase flows requires tuning.
  • Adhesion coefficient needs to be calibrated against experimental results or visually estimated.
  • Large negative pressures cannot be accurately handled by the current weakly compressible formulation without a strict total (particle) volume conservation.