Applied and Computational Mathematics (ACM)

Computational Magnetics

Many electro-technical devices such as e.g. printed circuit boards, electrical drives and antenna systems can be simulated on the basis of electrical circuits. However, the increasing frequencies and the decreasing size force designers to account for wave propagation effects, eddy-current effects, ferromagnetic saturation and hysteresis. For wave propagation effects and eddy-current effects, the results of stand-alone field simulation can be represented by an order-reduced equivalent model, which is then inserted in the overall circuit model. The representation of field-dependent nonlinearities and hysteresis effects, however, is not straightforward.

2D Simulation of a Transformer

2D Simulation of a Transformer

The coupled field and circuit simulation becomes troublesome when a large number of time steps is required. This occurs when e.g. simulating an electrical drive where the machine requires 10 periods of 50 Hz to reach nominal speed whereas the switching of the Insulated Gate Bipolar Transistors in the frequency converter switches at 20 kHz, necessitating a time steps in the order of a microsecond to be used in the simulation. Since the field model consists typically of a few million degrees of freedom, all those unknowns have to be solved in every time step. Fortunately, the relevant time constants in electrical-energy converter are in the range 50 Hz. Hence the field model does not have to be time-stepped at the same rate as the circuit model, in which fast switches are present. The use of adaptive multirate time-integration schemes can reduce the numerical complexity of the problem substantially.

Research Questions

Cooperation

Former and ongoing projects

Publications



2022

4841.

Lugo, Pedro L.; Straccia, V.G.; Rivela, Cynthia B.; Patroescu-Klotz, Iulia; Illmann, Niklas; Teruel, Mariano A.; Wiesen, Peter; Blanco, María B.
Diurnal photodegradation of fluorinated diketones (FDKs) by OH radicals using different atmospheric simulation chambers: Role of keto-enol tautomerization on reactivity
Chemosphere, 286 :131562
Januar 2022
ISSN: 00456535

4840.

Rohde, Martin; Barwari, Beawer; Burgmann, Sebastian; Janoske, Uwe
Droplet motion induced by superposition of shear flow and horizontal surface vibration
International Journal of Multiphase Flow, 155 :104163
2022
Herausgeber: Pergamon

4839.

McWalter, Thomas A; Kienitz, Jörg; Nowaczyk, Nikolai; Rudd, Ralph; Acar, Sarp K.
Dynamic initial margin estimation based on quantiles of Johnson distributions
Journal of Credit Risk, 18 :93–116
2022
Herausgeber: Incisive Media

4838.

Kienitz, Jörg; Lee, Gordon; Nowaczyk, Nikolai; Geng, N.
Dynamically controlled kernel estimation
Risk Cutting Edge, 1
2022
Herausgeber: Incisive Media

4837.

Kienitz, J.; Lee, G.; Nowaczyk, N.; Geng, N.
Dynamically Controlled Kernel Estimation
RISK, 1
2022

4836.

Felpel, Mike; Kienitz, Jörg; McWalter, Thomas
Effective Markovian projection: Application to CMS spread options and mid-curve swaptions
Quantitative Finance, 22 (6) :1169–1192
2022
Herausgeber: Routledge

4835.

Felpel, M.; Kienitz, J.; McWalter, T. A.
Effective Markovian projection: application to CMS spread options and mid-curve swaptions
Quantitative Finance, 22 (6) :1169-1192
2022
Herausgeber: Routledge

4834.

Reiners, Malena; Klamroth, Kathrin; Heldmann, Fabian; Stiglmayr, Michael
Efficient and sparse neural networks by pruning weights in a multiobjective learning approach
Computers & Operations Research :105676
2022

4833.

[german] Cornelius, Soraya; Bohrmann-Linde, Claudia
Einsatz eines digitalen & interaktiven Selbstlernbuchs zur Einführung in die organische Chemie - erste Erprobungen im Chemieunterricht und motivationale Betrachtungen
Chemie & Schule, 2022 (4) :5-9
2022

4832.

Clemens, Markus; Henkel, Marvin-Lucas; Kasolis, Fotios; Günther, Michael; De Gersem, Herbert; Schöps, Sebastian
Electromagnetic Quasistatic Field Formulations of Darwin Type
arXiv preprint arXiv:2204.06286
2022

4831.

Clemens, Markus; Henkel, Marvin-Lucas; Kasolis, Fotios; Günther, Michael; De Gersem, Herbert; Schöps, Sebastian
Electromagnetic quasistatic field formulations of Darwin type
Preprint :1–7
2022

4830.

Clemens, Markus; Henkel, Marvin-Lucas; Kasolis, Fotios; Günther, Michael; De Gersem, Herbert; Schöps, Sebastian
Electromagnetic quasistatic field formulations of Darwin type
Preprint :1–7
2022

4829.

Schillings, Claudia; Totzeck, Claudia; Wacker, Philipp
Ensemble-based gradient inference for particle methods in optimization and sampling
2022

4828.

Lübke, Steffen
Entwicklung und Optimierung einer kleintechnischen Anlage zur Behandlung galvanischer Abwässer mittels Aersolbasierter Eliminierung (ABE)
2022

4827.

Gaul, Daniela; Klamroth, Kathrin; Stiglmayr, Michael
Event-based MILP models for ridepooling applications
European Journal of Operational Research, 301 :1048-1063
2022

4826.

Glück, Jochen
Evolution equations with eventually positive solutions
Eur. Math. Soc. Mag. (123) :4--11
2022

4825.

Halffmann, Pascal; Schäfer, Luca E.; Dächert, Kerstin; Klamroth, Kathrin; Ruzika, Stefan
Exact algorithms for multiobjective linear optimization problems with integer variables - a state of the art survey
Journal of Multicriteria Decision Analysis, 29 :343–363
2022

4824.

Kalalian, Carmen; Grira, Asma; Illmann, Jan Niklas; Patroescu-Klotz, Iulia; El Dib, Gisèle; Coddeville, Patrice; Canosa, André; Wiesen, Peter; Aazaad, Basheer; Senthilkumar, Lakshmipathi; Roth, Estelle; Tomas, Alexandre; Chakir, Abdelkhaleq
Experimental and Theoretical Studies of Trans-2-Pentenal Atmospheric Ozonolysis
Atmosphere, 13 (2) :291
Februar 2022
ISSN: 2073-4433

4823.

Braschke, Kamil Oskar; Zoller, Julian; Freese, Florian; Dittler, Achim; Janoske, Uwe
Fast adhesion calculation for collisions between arbitrarily shaped particles and a wall
Powder Technology, 405 :117494
2022
ISSN: 0032-5910

4822.

Farkas, Bálint; Nagy, Béla; Révész, Szilárd Gy.
Fenton type minimax problems for sum of translates functions
2022

4821.

Könen, David; Schmidt, Daniel; Spisla, Christiane
Finding all minimum cost flows and a faster algorithm for the K best flow problem
Discrete Applied Mathematics, 321 :333-349
2022
ISSN: 0166-218X

4820.

Hensel, Hendrik; Henkel, Marvin-Lucas; Haussmann, Norman; Jörgens, Christoph; Stroka, Steven; Clemens, Markus
GPU-Accelerated Field Simulation of HVAC Gas Insulated Lines
2022 IEEE 20th Biennial Conference on Electromagnetic Field Computation (CEFC), Seite 1-2
2022

4819.

Teng, Long
Gradient boosting-based numerical methods for high dimensional backward stochastic differential equations
Appl. Math. Comput., 426 :127119
2022

4818.

Teng, Long
Gradient boosting-based numerical methods for high-dimensional backward stochastic differential equations
Applied Mathematics and Computation, 426 :127119
2022
Herausgeber: Elsevier

4817.

[german] Zeller, Diana
Heimische Ökosysteme erkunden. Mit Maphub kooperative, ökologische Kartierung umsetzen.
Digital Unterricht Biologie, 1 (1/2022) :10-11
Januar 2022