ECMI 2018 in Budapest

The 20th European Conference on Mathematics for Industry concluded on June, 22nd in Budapest, Hungary. The conference series is devoted to enforce the interaction between academy and industry, leading to innovations in both fields. These events have attracted leading experts from business, science and academia, and have promoted the application of novel mathematical technologies to industry. We organized a minisymposium on “Simulation, Optimization and Uncertainty Quantification of Field/Circuit Problems for E-Mobility Applications” and contributed three scientific talks
  • Kulchytska-Ruchka, Iryna ; Schöps, Sebastian ; Gander, Martin J. ; Niyonzima, Innocent : Convergence analysis of Parareal for systems with discontinuous inputs.
  • Cortes Garcia, Idoia ; De Gersem, Herbert ; Schöps, Sebastian : Generalised elements for the analysis of field/circuit coupled systems.
  • Bontinck, Zeger ; Corno, Jacopo ; Schöps, Sebastian ; De Gersem, Herbert : Iso-Geometric Analysis as a Tool for Simulating Electrical Machines.

Preisverleihung im hessischen Mathematikwettbewerb

Bildquelle: Hessenmetall

Ich war am Dienstag als Gastredner bei der Preisverleihung an die Kreissieger im hessischen Mathematikwettbewerb. Der Echo hat darüber in einem Zeitungsartikel berichtet. Zu meinem Vortrag steht da unter anderem…
In seinem abschließenden Vortrag zeigt Sebastian Schöps Möglichkeiten auf, wie Algorithmen und Berechnungen tatsächlich zum Einsatz kommen. Zum Beispiel könne mit Programmen simuliert werden, welche Schäden für die Gesundheit der Menschen entstehen, wenn sie permanent mit dem Handy am Ohr durch die Welt spazieren – ganz ohne Versuche direkt am Menschen.
Tatsächlich simuliert man nicht die Schäden, sondern die Erwärmung (oder noch genauer die Energiedeposition) als “multiphysikalisches Problem”, siehe z.B. die Veröffentlichung aus 2002 von Gjonaj, Bartsch, Clemens, Schupp, Weiland. Simulation oder nicht, es gibt bisher keinen wissenschaftlichen Nachweis über Schäden. Die aktuellen Grenzwerte und viele weitere Informationen zum Thema findet man z.B. beim Informationszentrum Mobilfunk.

Update: Mehr Informationen auf Hessenmetall.de.

The International Symposium on Electric and Magnetic Fields 2018 is over

The 11th International Symposium on Electric and Magnetic Fields, EMF 2018, was hosted in Darmstadt and concluded on Friday. The purpose of the Symposium was to throw a bridge between recent research advances in mathematical and numerical modelling of electromagnetic fields and the growing number of industrial problems requiring such techniques. There were 95 participants from 19 countries and 3 invited talks. The participants gave 26 oral presentations, presented 53 posters and drank 700 cups of coffee. Already these numbers imply that the conference was a great success. Now, we are looking forward to meet our colleagues in Marseille for the next edition organized by André Nicolet and co-workers.

A New Parareal Algorithm for Problems with Discontinuous Sources

We recently proposed a new Parareal algorithm for problems with discontinuous sources which are common in electrical engineering, e.g., when an electric device is supplied with a pulse-width-modulated signal. Our algorithm uses a smooth input for the coarse problem with reduced dynamics. In the new arXiv preprint 1803.05503 preprint an error estimates is derived that shows how the input reduction influences the overall convergence rate of the algorithm. The theoretical results are supported by numerical experiments, including an eddy current simulation of an induction machine.

Pressemitteilung zu PASIROM

Die technische Universität Darmstadt hat eine Pressemitteilung zu PASIROM veröffentlicht: Forschungsprojekt von Universitäten und Industriepartnern gestartet. Mit mathematischen Methoden das optimale Design für Energiewandler finden: Dieser Aufgabe widmet sich das gerade gestartete Forschungsprojekt PASIROM, an dem drei Universitäten und zwei Anwendungspartner beteiligt sind. Continue reading →

New paper on isogeometric analysis of electrical machines

Computer Methods in Applied Mechanics and Engineering has accepted our paper on Isogeometric analysis and harmonic stator–rotor coupling for simulating electric machines with DOI 10.1016/j.cma.2018.01.047. The paper proposes Isogeometric Analysis as an alternative to classical finite elements for simulating electric machines. Through the spline-based discretisation it is possible to parametrise the circular arcs exactly, thereby avoiding any geometrical error in the representation of the air gap where a high accuracy is mandatory.

Update: get the paper for free before April 10, 2018 at authors.elsevier.com.

First results on fast high-order IGABEM

We published a first preprint at arXiv on our research on Isogeometric BEM for Superconducting Cavities (DFG SCHO 1562/3-1 and KU 1553/4-1). In cooperation with the Computational Mathematics group in Basel we discuss the usage of higher order B-splines in view of regularity requirements, convergence of the solution within the domain and multipole compression techniques. Continue reading →

New paper on Waveform Relaxation for Multiscale Problems

jcp Our paper on Waveform Relaxation for the Computational Homogenization of Multiscale Magnetoquasistatic Problems (Innocent Niyonzima, Christophe Geuzaine, Sebastian Schöps) has been accepted by JCP:
This paper proposes the application of the waveform relaxation method to the homogenization of multiscale magnetoquasistatic problems. In the monolithic heterogeneous multiscale method, the nonlinear macroscale problem is solved using the Newton–Raphson scheme. The resolution of many mesoscale problems per Gauss point allows to compute the homogenized constitutive law and its derivative by finite differences. In the proposed approach, the macroscale problem and the mesoscale problems are weakly coupled and solved separately using the finite element method on time intervals for several waveform relaxation iterations. The exchange of information between both problems is still carried out using the heterogeneous multiscale method. However, the partial derivatives can now be evaluated exactly by solving only one mesoscale problem per Gauss point. Continue reading →