Study of a Self Heating Process of Tetrafluoroethylene by the Exothermic Dimerization Reaction to Octafluorocyclobutane
M. Beckmann-Kluge, H. Krause, V. Schröder, A. Acikalin, and J. Steinbach
Federal Institute for Materials Research and Testing, Berlin, Germany
Technical University Berlin, Berlin, Germany
The self heating process of Tetrafluoroethylene caused by an exothermic dimerization reaction was studied. The heat of reaction can lead to a thermal explosion by the decomposition of the Tetrafluoroethylene. Different reaction kinetics, including multistep kinetics, were used to describe the mass balance. The COMSOL Chemical Engineering Module was used to perform the simulation which was ...
P. Almeida, and M. Benilov
Departamento de Física. Universidade da Madeira, Portugal
It was suggested long ago that a theoretical model of a near-cathode region in a DC glow discharge admits multiple steady-state solutions describing different modes of currrent transfer. Even the most simple self-consistent models should admit such multiple solutions. In the present work, these solutions have been calculated for the first time with COMSOL Multiphysics.
D. Lahaye, D. Cvoric, S. de Haan, and J. Ferreira
Delft Institute of Applied Mathematics, Department of Electrical Engineering, Mathematics and Computer Sciences, TU Delft, The Netherlands
Electrical Power Processing Unit Department of Electrical Engineering, Mathematics and Computer Sciences, TU Delft, The Netherlands
Fault Current Limiters (FCLs) are expected to play an important role in the protection of future power systems due to the rising levels of the short-circuit currents. The inductive FCLs, comprising magnetic cores and one or more dc and ac windings, are particularly interesting because they inherently react on the fault. The so-called open-core FCL configuration employs only one magnetic core for ...
O. Geoffroy, and H. Rouch
INOPRO, Villard de Lans, France
The crystal growth industry uses high temperature processes. To improve production efficiency, a good knowledge of thermal effects is necessary. We show in this article a methodology to get reliable data by mixing simplified models, sensitivity studies and parameters adjustments. The precision is improved by comparison with experimental measurements.
B. Ottosson, Y. Jouahri, C. Rusu, and P. Enoksson
Imego AB, Gothenburg, Sweden
Chalmers University of Technology, Gothenburg, Sweden
The objective of this work has been to realize a feasibility study of a cooling device for a SQUID sensor using liquid nitrogen flowing through micro channels. The design consists of an epoxy cylindrical vacuum vessel skewed by a silicon microchannel heat sink. The SQUID sensor is situated directly on top of the microchannel heat sink. The device is used at room temperature and should be able to ...
Numerical Analysis of the Impact of Geometric Shape Patterns on the Performance of Miniaturized Chromatography Systems
R. Winz, E. von Lieres, and W. Wiechert
Department of Simulation, University of Siegen, Siegen, Germany
Institute of Biotechnology, Research Centre Jülich, Siegen, Germany
We have implemented a two dimensional chromatography model for the analysis and optimization of structured micro pillar arrays. Dynamic surface interaction of solved molecules is taken into account by the kinetic Langmuir model. Variations of the pillar array geometry lead to deviations in the outlet concentration profiles. These deviations cannot be described by the one dimensional models that ...
R. Umhack, M. Rainer, M. Tamerle, and G. Hillmer
Process-, Environmental- and Bio- technology, MCI - University of Applied Sciences, Innsbruck, Austria
A new type of radiator with a package of combs, to gain a larger area for heat exchange, instead of trapezoidal convector plates, is investigated. The main aim is to find the optimal comb diameter. To solve this problem, CFD (computational fluid dynamics) with COMSOL Multiphysics is used. A chart showing radiator power was produced, which includes radiator power for different temperatures and ...
A. Buchau, and W. Rucker
Institut für Theorie der Elektrotechnik, Universität Stuttgart, Germany
Augmented reality is predestined for visualization of electromagnetic fields in air or inside transparent matter. Real existing objects are studied and invisible electromagnetic fields are added as virtual objects. Hence, experts as well as students are able to connect electromagnetic fields easily with studied objects. They can concentrate on physical effects instead on reading figures. Here, an ...
M. Herring Jensen
Widex A/S, Vaerloese, Denmark
In this study we model the sound attenuation properties of a hearing aid earmold tube. The model includes thermoviscous acoustic effects and it couples structural vibrations to the external acoustic field. Moreover, the finite element domain is coupled at two boundaries with an electroacoustic model of a hearing aid and an acoustic 2-cc coupler.
M. Di Bari, and G. Zito
University of Bari, Italy
Many theoretical studies concerning lava tubes focus on the thermal disturbances generated on the earth surface. Recently a solution was suggested, where a lava tube located at a great depth h in the soil, where the ratio between h to the major axis of the ellipse a is higher than 10. However, lava tubes more frequently are located at shallower depths. In this work we ...