Krzysztof Wawrzyk, 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: kwawrzyk

Recent publications
1.Kowalczyk P., Rojek J., Stocki R., Bednarek T., Tauzowski P., Lasota R., Lumelskyy D., Wawrzyk K., NUMPRESS − integrated computer system for analysis and optimization of industrial sheet metal forming processes, HUTNIK - WIADOMOŚCI HUTNICZE, ISSN: 1230-3534, Vol.81, No.1, pp.56-63, 2014
Abstract:

The NUMPRESS System has been developed in IPPT PAN as a result of a project financially supported by European Regional Development Fund (within the Innovative Economy Programme) and is dedicated to small and middle enterprises dealing with sheet metal forming. The program consists of (i) an analytical module for analysis of forming processes with the finite element method, (ii) an optimization module controlling execution of the analytical module and performing optimization with respect to selected process parameters, in both deterministic and robust formulation, (iii) a reliability analysis module controlling execution of the analytical module to assess how random distribution of design parameters affects forming results, and (iv) a graphical user interface enabling communication between modules and easy definition of design parameters and optimization criteria. The analytical module consists of two independent programs up to the user's choice: NUMPRESS-Flow, a faster and less accurate program for implicit quasi-static analysis of rigid-viscoplastic shells (based on the flow approach) and NUMPRESS-Explicit, a program for explicit dynamical analysis of elastic-plastic and elastic-viscoplastic shells. Both programs are interfaced to a well-known commercial graphical pre- and postprocessor GiD. Fundamentals of formulations employed in the system and numerical examples are presented in the paper.

Keywords:

sheet metal forming, finite element method, deterministic and robust design optimization, reliability analysis

Affiliations:
Kowalczyk P.-IPPT PAN
Rojek J.-IPPT PAN
Stocki R.-IPPT PAN
Bednarek T.-IPPT PAN
Tauzowski P.-IPPT PAN
Lasota R.-IPPT PAN
Lumelskyy D.-IPPT PAN
Wawrzyk K.-IPPT PAN
2.Wawrzyk K., Kowalczyk P., Zmodyfikowany algorytm poszukiwania kontaktu w zagadnieniach tłoczenia blach, HUTNIK - WIADOMOŚCI HUTNICZE, ISSN: 1230-3534, Vol.LXXIX, pp.28-30, 2012
Abstract:

Niniejsza praca dotyczy procedury poszukiwania kontaktu w symulacji numerycznej procesu tłoczenia blach. W pracy zaproponowano poprawkę do standardowego algorytmu poszukiwania kontaktu, pozwalającą na wyeliminowanie możliwych błędów polegających na źle wskazanym elemencie kontaktowym, bądź wskazaniu braku takiego elementu, co w konsekwencji prowadzi do błędnych wyników symulacji. Ponadto w pracy przeanalizowano koszt numeryczny przedstawionego algorytmu.

Keywords:

analiza kontaktu, tłoczenie blach

Affiliations:
Wawrzyk K.-IPPT PAN
Kowalczyk P.-IPPT PAN
3.Laskowski R., Wawrzyk K., Comparison of two simple mathematical models for feed water heaters, Journal of Power Technologies, ISSN: 2083-4187, Vol.91, No.1, pp.14-22, 2011

Conference papers
1.Rojek J., Nosewicz S., Maździarz M., Kowalczyk P., Wawrzyk K., Lumelskyj D., Modeling of a Sintering Process at Various Scales, Procedia Engineering, ISSN: 1877-7058, DOI: 10.1016/j.proeng.2017.02.210, Vol.177, pp.263-270, 2017
Abstract:

This paper presents modeling of a sintering process at various scales. Sintering is a powder metallurgy process consisting in consolidation of powder materials at elevated temperature but below the melting point. Sintering models at the atomistic, microscopic and macroscopic scales have been presented. Sintering is a process governed by diffusion therefore the atomistic modeling using the molecular dynamics has been focused on investigation of the diffusion process. The micromechanical model has been developed within the framework of the discrete element method. It allows us to consider microstructure and its changes during sintering. The macroscopic model is based on the continuum phenomenological approach. It combines elastic, thermal and viscous creep deformation. The methodology to determine macroscopic quantities: stress, strains and constitutive viscous properties from the discrete element simulations has been presented. Possibilities of the developed models have been demonstrated by applying them to simulation of sintering of the intermetallic NiAl powder. Own experimental results have been used to calibrate and validate numerical models.

Keywords:

sintering, modeling, discrete element method, diffusion, molecular dynamics, macroscopic model

Affiliations:
Rojek J.-IPPT PAN
Nosewicz S.-IPPT PAN
Maździarz M.-IPPT PAN
Kowalczyk P.-IPPT PAN
Wawrzyk K.-IPPT PAN
Lumelskyj D.-IPPT PAN

Conference abstracts
1.Wawrzyk K., Nosewicz S., Rojek J., Kowalczyk P., A constitutive model and numerical simulation of sintering processes at macroscopic level, CMM-2017, 22nd International Conference on Computer Methods in Mechanics, 2017-09-13/09-16, Lublin (PL), pp.MS02-13-MS02-14, 2017
Abstract:

This document presents modelling of single-phase powder sintering processes at the macroscopic level. In particular, its constitutive formulation, numerical implementation and numerical test are described. Numerical tests were carried out for a cylindrical specimen under hydrostatic and uniaxial pressure. Results of macroscopic analysis are compared against the microscopic model results.

Keywords:

sintering porcesses, numerical analysis, multiscale modelling

Affiliations:
Wawrzyk K.-IPPT PAN
Nosewicz S.-IPPT PAN
Rojek J.-IPPT PAN
Kowalczyk P.-IPPT PAN
2.Nosewicz S., Rojek J., Maździarz M., Kowalczyk P., Wawrzyk K., Chmielewski M., Pietrzak K., Multiscale modeling of pressure-assisted sintering process, EUROMAT 2017, European Congress and Exhibition on Advanced Materials and Processes, 2017-09-17/09-22, Thessaloniki (GR), pp.1, 2017
3.Rojek J., Kowalczyk P., Nosewicz S., Jurczak K., Wawrzyk K., Micro-macro relationships from discrete element simulations of sintering, ECCOMAS 2016, European Congress on Computational Methods in Applied Sciences and Engineering, 2016-06-05/06-10, Hersonissos (GR), pp.1, 2016
Keywords:

sintering, discrete element method, multi-scale modeling

Affiliations:
Rojek J.-IPPT PAN
Kowalczyk P.-IPPT PAN
Nosewicz S.-IPPT PAN
Jurczak K.-IPPT PAN
Wawrzyk K.-IPPT PAN
4.Wawrzyk K., Kowalczyk P., Macroscopic constitutive model of sintering processes and its numerical implementation, SolMech 2016, 40th Solid Mechanics Conference, 2016-08-29/09-02, Warszawa (PL), No.P210, pp.1-2, 2016
Keywords:

sintering, constitutive model

Affiliations:
Wawrzyk K.-IPPT PAN
Kowalczyk P.-IPPT PAN
5.Rojek J., Nosewicz S., Maździarz M., Kowalczyk P., Wawrzyk K., Modelling of powder sintering at various scales, SolMech 2016, 40th Solid Mechanics Conference, 2016-08-29/09-02, Warszawa (PL), No.P193, pp.1-2, 2016
Keywords:

sintering, multiscale modelling

Affiliations:
Rojek J.-IPPT PAN
Nosewicz S.-IPPT PAN
Maździarz M.-IPPT PAN
Kowalczyk P.-IPPT PAN
Wawrzyk K.-IPPT PAN
6.Kowalczyk P., Rojek J., Stocki R., Bednarek T., Tauzowski P., Lasota R., Lumelskyy D., Wawrzyk K., NUMPRESS – integrated computer system for analysis and optimization of industrial sheet metal forming processes: examples of use, AutoMetForm/SFU 2014, New Materials for Vehicle Components, 2014-11-03/11-05, Freiburg (DE), pp.284-286, 2014
Abstract:

This paper presents NUMPRESS System that has been developed in IPPT PAN as a result of a project financially supported by European Regional Development Fund (within the Innovative Economy Programme) and is dedicated to small and middle enterprises dealing with sheet metal forming. It seems undoubted that efficient design of an industrial sheet forming process requires reliable computer simulations and a tool for numerical optimization of the process parameters. It has to be also admitted that. among small and medium enterprises (SME) in this industrial branch, there are many who do not use any such numerical tools in their practice.
Computer simulation of sheet metal forming processes is a very specific branch of computational mechanics. Finite element systems dedicated strictly to this kind of processes are needed and actually present on the market. Commercial systems (like Autoform, PAM-Stamp, Stampack, etc.) are, due to their prices, usually beyond financial ability of SME.

Design of the drawing process and tools, i.e. choice of proper values of several design parameters, require efficient optimization strategy. In this process, random character of at least some of the parameters has to be taken into account. In view of this fact, the traditional, deterministic approach to optimization is insufficient and elements of robust design optimization techniques and reliability analysis have to be included in the formulation of the optimization problem. It has to be admitted that, even if some of the mentioned commercial simulation systems offer numerical optimization modules, not all of them reach beyond the deterministic concept of the optimization process.

Keywords:

sheet metal forming, finite element method, deterministic and robust design optimization, reliability analysis

Affiliations:
Kowalczyk P.-IPPT PAN
Rojek J.-IPPT PAN
Stocki R.-IPPT PAN
Bednarek T.-IPPT PAN
Tauzowski P.-IPPT PAN
Lasota R.-IPPT PAN
Lumelskyy D.-IPPT PAN
Wawrzyk K.-IPPT PAN
7.Kowalczyk P., Rojek J., Stocki R., Bednarek T., Tauzowski P., Lasota R., Lumelskyy D., Wawrzyk K., NUMPRESS – integrated computer system for analysis and optimization of industrial sheet metal forming processes: numerical investigation of square cup drawing, SolMech 2014, 39th Solid Mechanics Conference, 2014-09-01/09-05, Zakopane (PL), pp.237-238, 2014
Abstract:

This paper presents basic features of the NUMPRESS system and some examples ofuse. The system has been developed at IPPT PAN as a result of a project financially supported by European Regional Development Fund and is dedicated to small and middle enterprises (SME) dealing with sheet metal forming. The program consists of (i) an analytical finite element method module (ii) an optimization module, (iii) a reliability analysis module, and (iv) a graphical user interface enabling communication between modules. The analytical module consists of two independent programs up to the user’s choice: NUMPRESS-Flow, a faster and less accurate program for implicit quasi-static analysis of rigid-viscoplastic shells (based on the flow approach) and NUMPRESS-Explicit, a program for explicit dynamical analysis of elastic-plastic shells. Both programs are interfaced to a well-known commercial graphical pre-and postprocessor GiD.

Keywords:

sheet metal forming, finite element method, deterministic and robust design optimization, reliability analysis

Affiliations:
Kowalczyk P.-IPPT PAN
Rojek J.-IPPT PAN
Stocki R.-IPPT PAN
Bednarek T.-IPPT PAN
Tauzowski P.-IPPT PAN
Lasota R.-IPPT PAN
Lumelskyy D.-IPPT PAN
Wawrzyk K.-IPPT PAN
8.Wawrzyk K., Kowalczyk P., Modified contact search algorithm for sheet metal forming, SolMech 2012, 38th Solid Mechanics Conference, 2012-08-27/08-31, Warszawa (PL), pp.68-69, 2012
Keywords:

finite element method, contact analysis, sheet metal forming

Affiliations:
Wawrzyk K.-IPPT PAN
Kowalczyk P.-IPPT PAN