Paweł Jarzębski, M.Sc., Eng.

Department of Information and Computational Science (ZIiNO)
Division of Computational Analysis of Advanced Structures (ZeKAZK)
position: doctoral student
telephone: (+48) 22 826 12 81 ext.: 183
room: 409
e-mail: pjarz

Recent publications
1.Jarzębski P., Wiśniewski K., Taylor R.L., On parallelization of the loop over elements in FEAP, COMPUTATIONAL MECHANICS, ISSN: 0178-7675, DOI: 10.1007/s00466-015-1156-z, Vol.56, pp.77-86, 2015
Abstract:

In this paper, we consider parallelization of the loop over elements using OpenMP in FEAP (Taylor, 2014), which is a research FE code, very popular at universities. Even for a serial version of FEAP (a cluster version also exists) such a parallelization is a non-trivial task due to the existing architecture of this code, which complicates efficient parallelization. First, we compare the serial version of FEAP to the parallel code Warp3D (Dodds et al., 2014), considering the usage of time and memory. As we found, Warp3D is much faster but uses more memory than FEAP. An analysis of Warp3D helps us to devise our method of parallelization of the loop over elements. Next, we describe several changes in FEAP, which were necessary to parallelize the loop over elements using OpenMP. In particular, the subroutine assembling elemental matrices is identified as crucial to good performance, and several directives for the mutual exclusion synchronization of OpenMP are implemented and tested. Finally, we demonstrate the performance of the parallelized FEAP, designated as ompFEAP, on numerical examples involving 3D and shell elements of FEAP as well as user’s elements. We conclude that ompFEAP, using the directive ATOMIC for synchronization of the assembling, provides a very good speedup and efficiency.

Keywords:

Parallelization, OpenMP, Finite element method, FEAP, 3D and shell elements

Affiliations:
Jarzębski P.-IPPT PAN
Wiśniewski K.-IPPT PAN
Taylor R.L.-University of California, Berkeley (US)

List of chapters in recent monographs
1.
472
Jarzębski P., Wiśniewski K., Advances in Mechanics: Theoretical, Computational and Interdisciplinary Issues, rozdział: Performance of the parallel FEAP in calculations of effective material properties using RVE, CRC Press/Balkema, Taylor & Francis Group, M. Kleiber et al. (Eds.), pp.241-244, 2016

Conference abstracts
1.Jarzębski P., Wiśniewski K., Evaluation of partial factorization for condensation of shell and solid-shell elemental matrices, SolMech 2016, 40th Solid Mechanics Conference, 2016-08-29/09-02, Warszawa (PL), No.P100, pp.1-2, 2016
Keywords:

finite element methods, solid-shell elements

Affiliations:
Jarzębski P.-IPPT PAN
Wiśniewski K.-IPPT PAN
2.Jarzębski P., Wiśniewski K., On calculation of effective material properties using RVE method by parallelized FE code for shell applications, PCM-CMM 2015, 3rd Polish Congress of Mechanics and 21st Computer Methods in Mechanics, 2015-09-08/09-11, Gdańsk (PL), pp.375-376, 2015
Abstract:

This paper concerns parallelization of an FE code for machines with shared memory in order to speed up computations of large models. We parallelized the loop over elements in the research code FEAP using OpenMP, which required several modifications of the code and a specific method of synchronization for assembling, for details see [2]. The parallel solver was also applied. We demonstrate performance of the parallelized FEAP, designated as ’ompFEAP’, in calculations of effective properties of materials using the RVE method. Two RVE examples are computed, for a heterogenous metal-ceramic composite and for a ceramic foam with a complicated micro-structure. We conclude that ompFEAP provides a very good speedup and efficiency causing only a small increase in memory usage.

Keywords:

parallelization, OpenMP, finite element method, FEAP, RVE, shells

Affiliations:
Jarzębski P.-IPPT PAN
Wiśniewski K.-IPPT PAN
3.Jarzębski P., Wiśniewski K., Corrected shape functions for six-node triangular element for heat conduction, CMM 2013, 20th International Conference on Computer Methods in Mechanics, 2013-08-27/08-31, Poznań (PL), pp.345-353, 2014
Abstract:

In this paper, we derived the corrected shape functions for 6-node triangular element using the concept proposed in (Celia & Gray 1984). These shape functions were implemented in the two-dimensional 6-node triangular element for heat conduction as a replacement of the isoparametric ones. The numerical tests indicate that, for distorted meshes, the new element is more accurate than the standard element. Comparisons of the accuracy of a range of triangular and quadrilateral elements also are provided.

Keywords:

Six-node triangular element, heat conduction, corrected shape functions, sensitivity to mesh distortion, patch test

Affiliations:
Jarzębski P.-IPPT PAN
Wiśniewski K.-IPPT PAN
4.Jarzębski P., Wiśniewski K., On parallelization of the loop over elements for composite shell computations, SolMech 2014, 39th Solid Mechanics Conference, 2014-09-01/09-05, Zakopane (PL), pp.227-228, 2014
5.Jarzębski P., Wiśniewski K., On corrected shape functions for six-node triangular elements applied to heat conduction problems, CMM 2013, 20th International Conference on Computer Methods in Mechanics, 2013-08-27/08-31, Poznań (PL), No.MS09, pp.11-12, 2013