https://www.asc.tuwien.ac.at/~schoeberl/wiki/index.php?title=Special:NewPages&feed=atom&hideredirs=1&limit=50&offset=&namespace=0&username=&tagfilter=Wiki - New pages [en]2024-03-28T15:12:48ZFrom WikiMediaWiki 1.28.0https://www.asc.tuwien.ac.at/~schoeberl/wiki/index.php/Projecthp-EMT4FSProjecthp-EMT4FS2022-12-13T16:20:23Z<p>Valentinh: </p>
<hr />
<div>__NOTOC__ {{DISPLAYTITLE: Effective Material Transformation for Ferromagnetic Sheets EMT4FS }}<br />
==== Project Manager ====<br />
<br />
* [http://www.asc.tuwien.ac.at/~schoeberl/wiki/index.php/Karl_Hollaus Dr. Karl Hollaus]<br />
Institute for Analysis and Scientific Computing <br><br />
Wiedner Hauptstrasse 8-10 <br><br />
A-1040 Vienna, Austria <br />
<br />
Tel: +43 1 58801 10116 <br><br />
Email: [mailto:karl.hollaus@tuwien.ac.atNOSPAMPLEASE karl.hollaus@tuwien.ac.at]<br />
<br />
==== Project Staff ====<br />
* [http://www.asc.tuwien.ac.at/~schoeberl/wiki/index.php/Markus_Sch%C3%B6binger Dipl.-Ing. Markus Schöbinger (Ph.D. student)]<br />
* [http://www.asc.tuwien.ac.at/~schoeberl/wiki/index.php/Valentin_Hanser Dipl.-Ing. Valentin Hanser (Ph.D. student)]<br />
<br />
==== Project Member ====<br />
* [http://www.asc.tuwien.ac.at/~schoeberl Univ.Prof. Dr. Joachim Schöberl]<br />
* Prof. Igor Tsukerman<sup>2</sup><br />
* Prof. Yilmaz Sozer<sup>2</sup><br />
<sup>2</sup>University of Akron, Ohio, USA<br />
<br />
==== Open Positions ====<br />
There are currently no vacant positions.<br />
<br />
==== Funding ====<br />
Fonds zur Förderung der wissenschaftlichen Forschung [http://www.fwf.ac.at/en/ FWF] <br> <br />
Grant number: P 36395 <br> <br />
Funding periode: from November 1, 2022 to October 31, 2025<br />
<br />
==== Abstract ====<br />
<br />
''Wider research context / theoretical framework:'' <br />
The computation of eddy currents (ECs) in laminated iron cores of electrical devices or in thin contacting ferromagnetic shielding sheets is of enormous importance. The overall dimensions of a single sheet are in the range of meters, whereas the thickness and the penetration depth are essentially smaller than one millimeter. Detailed finite element (FE) models of large electrical devices would yield extremely large equation systems (ESs) impossible to solve with reasonable computational effort. To avoid ill-conditioned ESs of shielding sheets and an unduly large number of FEs is very difficult. Accurate modeling of highly nonlinear and anisotropic materials with hysteresis is challenging.<br />
<br />
''Hypotheses / research questions / objectives:'' <br />
Multiscale and homogenization methods are currently one of the best methods to simulate the ECs in thin sheets efficiently. However, multiscale expansions, for instance, to cope with small penetration depths, are not necessarily stable and the number of unknowns grows linearly with the order of the approach leading to rising computational costs. Generally strong field variations across a sheet require many integration points which makes the assembling of FE systems expensive especially in case of hysteresis. The aim is to accurately compute ECs in thin highly nonlinear sheets and associated stray fields by novel methods requiring radically less FEs, that work with only a scalar potential at the best and avoid expensive FE system assembling.<br />
<br />
''Approach / methods:'' <br />
Homogenization replaces a given fine scale hetero-structure with a homogeneous one such that certain quantities, e.g. reaction fields and losses, remain approximately the same. A low frequency excitation induces ECs in laminated nonlinear magnetic and conducting media. It turns out that the appropriate coarse-scale (homogeneous) model does not include ECs and is, counter-intuitively, magnetostatic, with an effective complex-valued BH-curve whose real and imaginary parts accurately represent active and reactive power in the sample. A suitable cell problem has to be solved at negligibly small costs to obtain the effective material transformation including hysteresis.<br />
<br />
''Level of originality / innovation:'' <br />
There are known methods where complex BH-curves were used in connection with hysteresis, but here they are introduced in the context of homogenization. Contrary to most established homogenization theories, the physical nature of the problem is changed. We solve an eddy current problem on the fine scale and a static magnetic field problem on the coarse (homogenized) scale. Thus, problems are solved in a fundamentally different way than before.<br />
<br />
The project will be carried out by the applicant and the doctoral candidates.<br />
<br />
==== Software ====<br />
Finite element package [https://ngsolve.org/ ngsolve] for electromagnetic problems.</div>Karlhttps://www.asc.tuwien.ac.at/~schoeberl/wiki/index.php/Matthias_RambausekMatthias Rambausek2022-09-19T12:50:59Z<p>Michaeln: /* Publications (peer reviewed) */</p>
<hr />
<div>__NOTOC__ {{DISPLAYTITLE: Dr.-Ing. Matthias Rambausek}}<br />
<br />
{| cellpadding="6" cellspacing="0" <br />
|-<br />
| <html> <img src="https://www.asc.tuwien.ac.at/data/fotos/scicomp/rambausek_matthias.jpg" width="120"> </html> <br />
| &nbsp;<br />
| rowspan=2 valign="center" |<br />
<br />
==== Contact ====<br />
Institute for Analysis and Scientific Computing <br \><br />
Wiedner Hauptstrasse 8-10 <br \><br />
1040 Wien, Austria <br \><br />
<br \><br />
Room: DA 03 H22<br \><br />
Email: [mailto:matthias.rambausek@tuwien.ac.at matthias.rambausek@tuwien.ac.at]<br \><br />
<br \><br />
[https://scholar.google.at/citations?user=FQx3H6wAAAAJ&hl=de Google Scholar]<br />
[https://orcid.org/my-orcid?orcid=0000-0002-4528-1737 Orcid]<br />
|-<br />
|}<br />
<br />
===Micro CV===<br />
2008 to 2013: BSc and MSc from TU Graz, Master Thesis on variational r-adaptivity at the Institute of Strength of Material<br />
<br \><br />
2015 to 2019: PhD student at the University of Stuttgart, Institute of Applied Mechanics, Chair of Material Theory (Prof. Miehe, Prof. Keip); member of the SimTech Cluster of Excellence graduate school<br />
<br \><br />
2019 to 2020: Research Engineer at the Ecole Polytechnique (Palaisau, France), Laboratory of Solid Mechanics, Group of Prof. Danas<br />
<br \><br />
Feb. 2020: Defense of PhD Thesis on [http://elib.uni-stuttgart.de/handle/11682/11059 Magneto-Electro-Elasticity across scales] at the University of Stuttgart<br />
<br \><br />
2020 to 2021: Research Engineer / Post-Doc at the Ecole Polytechnique (Palaisau, France), Laboratory of Solid Mechanics, Group of Prof. Danas<br />
<br \><br />
2022 to now: Post-Doc at the TU Wien, Institute of Analysis and Scientific Computing, [https://www.asc.tuwien.ac.at/?id=contact&name=sch%C3%B6berl Group of Prof. Schöberl]<br />
<br />
===Research Interests===<br />
*Numerical multiscale modeling of highly deformable materials, in particular magnetorheological elastomers<br />
*Computer (FEM) simulations of strongly coupled multiphysics problems<br />
<br />
===Publications (peer reviewed)===<br />
#M. Rambausek and J. Schöberl (2023). "Curing spurious magneto-mechanical coupling in soft non-magnetic materials". International Journal for Numerical Methods in Engineering [http://dx.doi.org/10.1002/nme.7210 IJNME (open access)]"<br />
#M. Rambausek, D. Mukherjee and K. Danas (2022). "A computational framework for magnetically hard and soft viscoelastic magnetorheological elastomers" Computer Methods in Applied Mechanics and Engineering [http://dx.doi.org/10.1016/j.cma.2021.114500 CMAME (open access)]<br />
#D. Mukherjee, M. Rambausek and K. Danas (2021). "An explicit dissipative model for isotropic hard magnetorheological elastomers" Journal of the Mechanics and Physics of Solids [https://www.sciencedirect.com/science/article/pii/S0020746220302705?via%3Dihub JMPS] ([https://www.kostasdanas.com/kdanas_files/ArMRDJMPS2021_hMREs.pdf preprint])<br />
#M. Rambausek, and K. Danas (2021). "Bifurcation of magnetorheological film-substrate elastomers subjected to biaxial pre-compression and transverse magnetic fields" International Journal of Non-Linear Mechanics [http://dx.doi.org/10.1016/j.ijnonlinmec.2020.103608 IJNLM] ([https://www.kostasdanas.com/kdanas_files/ArRDIJNM2021.pdf preprint])<br />
#L. T. K. Nguyen, M. Rambausek and M.-A. Keip (2020). "Variational framework for distance-minimizing method in data-driven computational mechanics" Computer Methods in Applied Mechanics and Engineering [http://dx.doi.org/10.1016/j.cma.2020.112898 CMAME]<br />
#M. Rambausek, F.S. Göküzüm, L.T.K. Nguyen and M.-A. Keip (2019). "A two-scale FE-FFT approach to nonlinear magneto-elasticity" International Journal for Numerical Methods in Engineering [http://dx.doi.org/10.1002/nme.5993 IJNME]<br />
#M. Rambausek and M.-A. Keip (2018). "Analytical estimation of non-local deformation-mediated magneto-electric coupling in soft composites" Proceedings of the Royal Society of London A: Mathematical, Physical and Engineering Sciences [http://dx.doi.org/10.1098/rspa.2017.0803 RPSA]<br />
#M.-A. Keip and M. Rambausek (2017). "Computational and analytical investigations of shape effects in the experimental characterization of magnetorheological elastomers". International Journal of Solids and Structures [http://dx.doi.org/10.1016/j.ijsolstr.2017.04.012 IJSS]<br />
#M.-A. Keip and M. Rambausek (2016). "A multiscale approach to the computational characterization of magnetorheological elastomers". International Journal for Numerical Methods in Engineering [http://dx.doi.org/10.1002/nme.5178 IJNME]<br />
<br />
===Proceedings and Conference Papers===<br />
#K. Škardová, M. Rambausek, R. Chabiniok and M. Genet (2019). "Mechanical and Imaging Models-Based Image Registration" In VipIMAGE 2019, edrs. J.M.R.S Tavares and J.R.M. Natal, 77–85. Lecture Notes in Computational Vision and Biomechanics. Springer International Publishing [http://dx.doi.org/10.1007/978-3-030-32040-9_9 VipImage]<br />
#L.T.K. Nguyen, M. Rambausek and M.-A. Keip (2018). "A variational framework for distance-minimizing data-driven method for linear elasticity" Proceedings in Applied Mathematics and Mechanics [http://dx.doi.org/10.1002/pamm.201800354 PAMM]<br />
#O. Nadgir, M. Rambausek and M.-A. Keip (2018). "Computational homogenization of nematic liquid crystal elastomers based on Landau-de-Gennes theory" Proceedings in Applied Mathematics and Mechanics [http://dx.doi.org/10.1002/pamm.201800318 PAMM]<br />
#M. Rambausek and M.-A. Keip (2018). "Strain-mediated magneto-electric coupling in soft composites" Proceedings of the Third Seminar on the Mechanics of Multifunctional Materials [https://www.uni-due.de/imperia/md/content/mechanika/smmm3/smmm3_proceedings.pdf SMMM]<br />
#M. Rambausek and M.-A. Keip (2018). "Magneto-electro-active polymers: material properties and structural effects" Proceedings in Applied Mathematics and Mechanics [http://dx.doi.org/10.1002/pamm.201710242 PAMM]<br />
#M. Rambausek and M.-A. Keip (2017)."Micro-and macrostructural magneto-electric coupling in soft composites" In: 7th GACM Colloquium on Computational Mechanics for Young Scientists from Academia and Industry [http://dx.doi.org/10.18419/opus-9334 GACM]<br />
#M. Rambausek, M.-A. Keip and C. Miehe (2016). "A multiscale view on shape effects in the computational characterization of magnetorheological elastomers" Proceedings in Applied Mathematics and Mechanics [http://dx.doi.org/10.1002/pamm.201610180 PAMM]<br />
#M.-A. Keip and M. Rambausek (2015). "On the generation of soft magneto-electric effects through Maxwell interactions" Proceedings in Applied Mathematics and Mechanics [http://dx.doi.org/10.1002/pamm.201510145 PAMM]<br />
#M. Rambausek (2014). "Advanced Solution Strategies for r-Adaptive Finite Element Analysis" Proceedings in Applied Mathematics and Mechanics [http://dx.doi.org/10.1002/pamm.201410116 PAMM]<br />
<br />
<br />
===Software and Tools===<br />
*Miscellaneous contributions to the open source FEM software [https://ngsolve.org/ Netgen/NGSolve]<br />
*Main developer of the material modeling toolbox [https://gitlab.com/materiaux materiaux]<br />
<br />
<br />
===Teaching in winter term 2022===<br />
Modeling of nonlinear coupled field problems [https://tiss.tuwien.ac.at/course/courseDetails.xhtml?courseNr=101976&semester=2022W lecture] and [https://tiss.tuwien.ac.at/course/courseDetails.xhtml?courseNr=101978&semester=2022W exercise]</div>Michaeln