Two subsequent presentations on the 13th UnTRIM Workshop 2016 with the same title* Efficient river modelling applying subgrid technology (UnTRIM2)*, the first part concerning *concept and grids,* presented by Regina Patzwahl, and the second part concerning *results,* presented by Jacek A. Jankowski. Continue reading

# Tag Archives: unstructured grid

# Parallel implementation of a non-hydrostatic model for free surface flows with semi-Lagrangian advection treatment

*Jacek A. Jankowski*

**Abstract.** The parallel implementation of an unstructured-grid, three-dimensional, semi-implicit finite difference and finite volume model for the free surface Navier-Stokes equations (UnTRIM) is presented and discussed. The new developments are aimed to make the code available for high performance computing in order to address larger, complex problems in environmental free surface flows. Continue reading

# Verification and validation of the parallel UnTRIM

*Jacek A. Jankowski. *Verification and validation of the parallel UnTRIM, 5th UnTRIM Workshop, Trento, 19-21 May 2008.

A new UnTRIM version has been released (see Casulli 2008), featuring better data locality, improved interpolations in the advection scheme and, the most important, a radically new mass-conservative iterative approach to drying and wetting treatment based on Newton iterations with a proven convergence. In the presentation, detailed issues detected during the verification and validation of the refreshed MPI-parallel “2009” version of UnTRIM are presented, treated and resolved. Continue reading