TY - JOUR A1 - Alebouyeh Samami, Behzad A1 - Pieper, Martin A1 - Breitbach, Gerd A1 - Hodapp, Josef T1 - Heat production in the windings of the stators of electric machines under stationary condition JF - Heat and mass transfer N2 - In electric machines due to high currents and resistive losses (joule heating) heat is produced. To avoid damages by overheating the design of effective cooling systems is required. Therefore the knowledge of heat sources and heat transfer processes is necessary. The purpose of this paper is to illustrate a good and effective calculation method for the temperature analysis based on homogenization techniques. These methods have been applied for the stator windings in a slot of an electric machine consisting of copper wires and resin. The key quantity here is an effective thermal conductivity, which characterizes the heterogeneous wire resin-arrangement inside the stator slot. To illustrate the applicability of the method, the analysis of a simplified, homogenized model is compared with the detailed analysis of temperature behavior inside a slot of an electric machine according to the heat generation. We considered here only the stationary situation. The achieved numerical results are accurate and show that the applied homogenization technique works in practice. Finally the results of simulations for the two cases, the original model of the slot and the homogenized model chosen for the slot (unit cell), are compared to experimental results. Y1 - 2014 U6 - http://dx.doi.org/10.1007/s00231-014-1371-8 SN - 0947-7411 (Print) ; 1432-1181 (E-Journal) VL - 50 SP - 1707 EP - 1716 PB - Springer CY - Heidelberg ER - TY - CHAP A1 - Pieper, Martin A1 - Schulz, Silvia T1 - Teaching Simulation Methods with COMSOL Multiphysics N2 - This paper describes two courses on simulation methods for graduate students: “Simulation Methods” and “Simulation and Optimization in Virtual Engineering” The courses were planned to teach young engineers how to work with simulation software as well as to understand the necessary mathematical background. As simulation software COMSOL is used. The main philosophy was to combine theory and praxis in a way that motivates the students. In addition “soft skills” should be improved. This was achieved by project work as final examination. As underlying didactical principle the ideas of Bloom’s revised taxonomy were followed. The paper basically focusses on educational aspects, e.g. how to structure the course, plan the exercises, organize the project work and include practical COMSOL examples. KW - COMSOL Multiphysics KW - Optimization module KW - LiveLink for MATLAB KW - Bloom Taxonomy KW - education Y1 - 2014 ER - TY - JOUR A1 - Jildeh, Zaid B. A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Pieper, Martin T1 - Simulating the electromagnetic‐thermal treatment of thin aluminium layers for adhesion improvement JF - Physica status solidi (a) N2 - A composite layer material used in packaging industry is made from joining layers of different materials using an adhesive. An important processing step in the production of aluminium-containing composites is the surface treatment and consequent coating of adhesive material on the aluminium surface. To increase adhesion strength between aluminium layer and the adhesive material, the foil is heat treated. For efficient heating, induction heating was considered as state-of-the-art treatment process. Due to the complexity of the heating process and the unpredictable nature of the heating source, the control of the process is not yet optimised. In this work, a finite element analysis of the process was established and various process parameters were studied. The process was simplified and modelled in 3D. The numerical model contains an air domain, an aluminium layer and a copper coil fitted with a magnetic field concentrating material. The effect of changing the speed of the aluminium foil (or rolling speed) was studied with the change of the coil current. Statistical analysis was used for generating a general control equation of coil current with changing rolling speed. Y1 - 2015 U6 - http://dx.doi.org/10.1002/pssa.201431893 SN - 1862-6319 VL - Vol. 212 IS - 6 SP - 1234 EP - 1241 PB - Wiley CY - Weinheim ER - TY - CHAP A1 - Kremers, Alexander A1 - Pieper, Martin T1 - Simulation and Verification of Bionic Heat Exchangers with COMSOL Multiphysics® Software T2 - COMSOL Conference 2015 User Presentations ; COMSOL Conference 2015 Grenoble October 14 - 16, 2015 - World Trade Center, Grenoble, France Y1 - 2015 PB - COMSOL CY - Göttingen ; Berlin ER - TY - CHAP A1 - Stollenwerk, Dominik A1 - Rieke, C. A1 - Dahmen, Markus A1 - Pieper, Martin T1 - Biogas Production Modelling : A Control System Engineering Approach T2 - IOP Conference Series: Earth and Environmental Science. Bd. 32 Y1 - 2016 U6 - http://dx.doi.org/10.1088/1755-1315/32/1/012008 SN - 1755-1315 N1 - ICARET 2016, International Conference on Advances in Renewable Energy and Technologies, Putrajaya, MY, Feb 23-25, 2016 SP - 012008/1 EP - 012008/4 ER - TY - CHAP A1 - Geisler, Simon A1 - Pieper, Martin T1 - Mathematik PLuS als E-Book. Kann ein E-Book zur Ingenieursmathematik alle Lerntypen ansprechen? T2 - Das elektronische Schulbuch 2016 Y1 - 2017 SN - 978-3-643-13475-2 SP - 99 EP - 111 PB - LIT Verlag CY - Berlin ER - TY - CHAP A1 - Pieper, Martin A1 - Wählisch, Georg T1 - Mehrwert von E-Learning durch fächerübergreifenden Einsatz T2 - Teaching is Touching the Future & ePS 2016 - Kompetenzorientiertes Lehren, Lernen und Prüfen Y1 - 2017 SN - 978-3-946017-05-9 SP - 193 EP - 196 PB - UVW Universitätsverlag Webler CY - Bielefeld ER - TY - BOOK A1 - Pieper, Martin T1 - Mathematische Optimierung: Eine Einführung in die kontinuierliche Optimierung mit Beispielen Y1 - 2017 SN - 978-3-658-16975-6 U6 - http://dx.doi.org/10.1007/978-3-658-16975-6 PB - Springer Fachmedien CY - Wiesbaden ER - TY - JOUR A1 - Rieke, Christian A1 - Stollenwerk, Dominik A1 - Dahmen, Markus A1 - Pieper, Martin T1 - Modeling and optimization of a biogas plant for a demand-driven energy supply JF - Energy N2 - Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process. This paper provides a new model of a biogas plant, which is as accurate as the standard ADM1 model. The advantage compared to ADM1 is that it is based on only four parameters compared to 28. Applying this model, an optimization was installed, which allows a demand-driven supply by biogas plants. Finally the results are confirmed by several experiments and measurements with a real test plant. Y1 - 2018 U6 - http://dx.doi.org/10.1016/j.energy.2017.12.073 SN - 0360-5442 VL - 145 SP - 657 EP - 664 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Pieper, Martin T1 - Digitale Hochschullehre in mathematischen und mathematikdidaktischen Veranstaltungen T2 - Beiträge zum Mathematikunterricht 2018 : Vorträge zur Mathematikdidaktik und zur Schnittstelle Mathematik/Mathematikdidaktik auf der gemeinsamen Jahrestagung GDM und DMV 2018 (52. Jahrestagung der Gesellschaft für Didaktik der Mathematik). Bd. 1 Y1 - 2018 SN - 978-3-95987-089-4 SP - 105 EP - 106 PB - WTM-Verlag CY - Münster ER -