What's new in nanoFluidX 2021.2

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New Features

• Extractor – the extractor feature is in its essence an advanced probe capability. What distinguishes it from the regular probe capability in nanoFluidX is that the extractor supplies an .stl mesh of arbitrary shape to the solver and all the desired diagnostics are then measured on this .stl mesh. If the .stl file is just a planar surface in the middle of the fluid flow – various pressures and mass flows can be measured using the extractor tool. If the supplied .stl is actually that of the geometry, various forms of Fluid Contact Time can be measured as well as other physical variables directly on the mesh surface.
• Frame suite – Temporal frame – (also known as static frame) Frame suite was specifically developed to tackle automotive water wading cases where there is a strong requirement to simulate the car entering the water, moving through a channel of a specified water depth and exiting the water. Temporal frame (static frame) is complementing the previously introduced sliding frame (nanoFluidX 2021.1) by supporting a static car body with a moving floor. While such simulations were in principle always theoretically possible in nanoFluidX, the frame suite makes such simulations significantly more computationally efficient and easier to set up.
• nFX[c] exporting Ensight Gold format – In order to allow the user more freedom in the choice of post-processing tools, as well as for reasons of internal development support, nFX[c] will from now on support Ensight Gold output format.
• Polite simulation stop – while it was always possible to stop a running nanoFluidX simulation using ABORTFILE, this feature has now been improved to include writing of the recon files upon the simulation halt. This is triggered by creating a SAVEABORTFILE in the running folder.
• nFX[c] support for the frame feature post-processing – the previous version of nFX[c] in combination with a water wading simulation using a sliding frame feature of nanoFluidX did not result in the desired behavior, because nFX[c] could not accommodate the moving domain (sliding frame). Improvements have been made to nFX[c] to accommodate this particular use case.
• Open MPI 4.0.6 and UCX 1.10.1 – Using the latest available OpenMPI and UCX libraries to keep up to date with the rapidly developing hardware and maintain nanoFluidX’s signature high performance.

Enhancements

• Impose region definitions – Impose regions have become an important nanoFluidX feature which is used in daily by our customers. Based on the lessons learned over the past several years, we have further improved the impose regions by allowing for more flexibility in terms of possible options and scenarios. An important change is the introduction of the PARALLELEPIPED shape (of which CUBOID is a special case). The new formulation of the impose regions is presented in detail in the user guide. Please note that for backward compatibility we have maintained the old impose region definitions in 2021.2, but the old definitions will be deprecated in the 2022.0 release of nanoFluidX.