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 - JOUR A1 - Alexopoulos, Spiros A1 - Breitbach, Gerd A1 - Hoffschmidt, Bernhard A1 - Stobbe, P. T1 - Computational fluid flow of porous resic ceramic filtering modules and optimization of the channel edge form geometry JF - Proceedings : April 14 - 18, 2008, Leipzig, Germany / hosted by VDI, Society for Chemical and Process Engineering . Vol 2 Y1 - 2008 N1 - Verein Deutscher Ingenieure ; World Filtration Congress ; (10 : ; 2008.04.14-18 : ; Leipzig) ; WFC ; (10 : ; 2008.04.14-18 : ; Leipzig) SP - 300 EP - 304 PB - Filtech Exhibitions CY - Meerbusch ER - TY - JOUR A1 - Alexopoulos, Spiros A1 - Breitbach, Gerd A1 - Hoffschmidt, Bernhard A1 - Stobbe, P. T1 - Optimization of the geometry of porous SiC ceramic filtering modules using numerical methods JF - Developments in porous, biological and geopolymer ceramics : a collection of papers presented at the 31st International Conference on Advanced Ceramics and Composites, January 21 - 26, 2007, Daytona Beach, Florida ; [papers presented at the Symposium on Porous Ceramics: Novel Developments and Applications] / ed.: Manuel Brito ... Vol. ed.: Jonathan Salem ... The American Ceramics Society Y1 - 2008 SN - 9780470196403 N1 - Ceramic engineering and science proceedings ; 28,9 SP - 95 EP - 104 PB - Wiley CY - Hoboken, NJ ER - TY - JOUR A1 - Alexopoulos, Spiros A1 - Hoffschmidt, Bernhard T1 - Solar tower power plant in Germany and future perspectives of the development of the technology in Greece and Cyprus JF - Renewable Energy . 35 (2010), H. 7 Y1 - 2010 SN - 0960-1481 SP - 1352 EP - 1356 ER - TY - JOUR A1 - Alexopoulos, Spiros A1 - Hoffschmidt, Bernhard T1 - Advances in solar tower technology JF - Wiley interdisciplinary reviews : Energy and Environment : WIREs Y1 - 2017 U6 - http://dx.doi.org/10.1002/wene.217 SN - 2041-840X VL - 6 IS - 1 SP - 1 EP - 19 PB - Wiley CY - Weinheim ER - TY - JOUR A1 - Arpshofen, Ingo A1 - Pool, M. J. A1 - Sommer, Ferdinand A1 - Gerling, Ulrich A1 - Predel, Bruno A1 - Schultheiss, Emil T1 - Determination of the integral mixing enthalpies in the Cu-Pd-Si liquid ternary alloy system at 1600 K JF - Zeitschrift für Metallkunde : international journal of materials research and advanced techniques. Bd. 74, H. 1 Y1 - 1983 SN - 0044-3093 ; 0179-4841 SP - 25 EP - 32 ER - TY - JOUR A1 - Balewski, J. A1 - Brauksiepe, S. A1 - Hardt, Arno T1 - Threshold measurements at the internal experimental facility COSY-11 / J. Balewski [u.a.] JF - Nuclear physics A. Vol. 626, iss. 1-2 Y1 - 1997 SN - 1873-1554 (E-Journal) ; 0375-9474 (Print) SP - 85 EP - 92 ER - TY - JOUR A1 - Bansal, N. K. A1 - Müller, C. A1 - Vieira, M. E. A1 - Faber, Christian A1 - Schwarzer, Klemens T1 - Thermal performance of a rock bed storage system JF - Proceedings : University of Stuttgart, Germany, August 28th until September 1st, 2000 / Terrastock 2000, 8th International Conference on Thermal Energy Storage. Ed.: M. Benner ... - Vol. 1 Y1 - 2000 SN - 3-9805274-1-7 N1 - Terrastock <2000, Stuttgart> ; Institut für Thermodynamik und Wärmetechnik SP - 433 EP - 439 PB - Inst. für Thermodynamik und Wärmetechnik CY - Stuttgart ER - TY - JOUR A1 - Barsov, S. A1 - Bechstedt, U. A1 - Hardt, Arno T1 - ANKE, a new facility for medium energy hadron physics at COSY-Jülich / S. Barsov [u.a.] JF - Nuclear instruments and methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. Vol. 462, iss. 3 Y1 - 2001 SN - 0167-5087 (Print) ; 0168-9002 (E-journal) SP - 364 EP - 381 ER - TY - JOUR A1 - Baumgartner, Werner A1 - Fidler, Florian A1 - Weth, Agnes A1 - Habbecke, Martin A1 - Jakob, Peter A1 - Butenweg, Christoph A1 - Böhme, Wolfgang T1 - Investigating the locomotion of the sandfish in desert sand using NMR-Imaging JF - PLOS ONE N2 - The sandfish (Scincus scincus) is a lizard having the remarkable ability to move through desert sand for significant distances. It is well adapted to living in loose sand by virtue of a combination of morphological and behavioural specializations. We investigated the bodyform of the sandfish using 3D-laserscanning and explored its locomotion in loose desert sand using fast nuclear magnetic resonance (NMR) imaging. The sandfish exhibits an in-plane meandering motion with a frequency of about 3 Hz and an amplitude of about half its body length accompanied by swimming-like (or trotting) movements of its limbs. No torsion of the body was observed, a movement required for a digging-behaviour. Simple calculations based on the Janssen model for granular material related to our findings on bodyform and locomotor behaviour render a local decompaction of the sand surrounding the moving sandfish very likely. Thus the sand locally behaves as a viscous fluid and not as a solid material. In this fluidised sand the sandfish is able to “swim” using its limbs. KW - magnetic resonance imaging KW - body limbs KW - swimming KW - lizards KW - deserts Y1 - 2008 U6 - http://dx.doi.org/10.1371/journal.pone.0003309 SN - 1932-6203 VL - 3 IS - 10 PB - Plos CY - San Francisco, California, US ER -