Category Archives: Presentations

UnTRIM parallelization with message passing

Jacek A. Jankowski. UnTRIM parallelization with message passing, 2nd UnTRIM Workshop, Sirmione, 23-25 May 2005.

The main ideas behind the parallelisation of UnTRIM applying the domain decomposition method and the message passing (MPI) are discussed. The issues concerning the mesh partitioning, point-to-point communication over the mesh-overlapping areas (halos) for purely triangular and mixed (triangles and quadrangles) meshes and the problems connected with the Lagrangian advection scheme are thoroughly described. Continue reading →

UnTRIM applications for fluvial flows

Jacek A. Jankowski. UnTRIM applications for fluvial flows, 1st UnTRIM Workshop, Verona, 7-9 June 2004.

Attracted by the proven and excellent mathematical properties of the scheme and the ongoing OpenMP parallelisation of the UnTRIM code, BAW Karlsruhe has initiated an internal investigation to assess the feasibility of the freshly developed code for the engineering applications concerning river flows. Continue reading →

Developments concerning parallel computing with the Telemac System

Jacek A. Jankowski. Developments concerning parallel computing with the Telemac System, 10th Telemac User Club, Chamrousse, 9-10 October 2003.

BAW is one of the a few Telemac users applying the code on high performance computers (HPC), presently all of them parallel, in their sites in Hamburg (SGI Origin 3000), Karlsruhe (SGI Origin 2000) and also by DWD in Offenbach (IBM RS/6000 SP). The presentation addresses the specific methodology, issues and developments concerning HPC: Continue reading →

Coupling Telemac and Sisyphe internally

Jacek A. Jankowski. Coupling Telemac and Sisyphe internally, 9th Telemac User Club, Karlsruhe, 17-18 October 2002.

One of the disadvantages of the Telemac system is the traditional public library software structure based on of freely linkable Fortran functions with open parameter lists, being a legacy from the original Fortran-77 development in 1980-years. Fortran-90 modules are presently applied only for providing global variables of the system components, which is an incomplete solution. This works well with vertical programs-libraries hierarchy, but when a horizontal coupling between libraries or programs is necessary, awkward and unnecessary problems appear, alone due to the overlapping names of variables and the input/output conflicts.

The presentation proposes the encapsulation of the Telemac system principal components in the form of proper Fortran-90 modules providing correct module interfaces. Continue reading →

Developing an advection scheme for Telemac-2D based on the 2nd order characteristics method

Jacek A. Jankowski and Andreas Malcherek.

Developing an advection scheme for Telemac-2D based on the 2nd order characteristics method, 8th Telemac User Club, Chatou, 15-16 November 2001.

One of the best method of improving the accuracy of the advection scheme based on method of characterictics is to improve the interpolation of advected variables on the feet of the traced-back characteristic curves. The results of applying the second order interpolation in broader element patches are compared with the presently applied single-element linear interpolation and the SUPG method. Continue reading →