Multiphysics Simulation of Thermoelectric Systems - Modeling of Peltier-Cooling and Thermoelectric Generation
Fraunhofer-Institute for Physical Measurement-Techniques (IPM), Freiburg, Germany
Electro-thermal interaction is commonly considered only as a matter of joule heating. In addition, the Seebeck-, Peltier- and Thompson-Effects are significant in materials with high thermoelectric figure of merit Z. These thermoelectric materials have a high Seebeck-coefficient α, a good electric conductivity σ, and a poor thermal conductivity λ. They have widespread areas of ...
A. Weddemann, and V. Thümmler
Bielefeld University, Germany
ALE-methods are frequently used to solve systems of partial differential equations (PDEs) on moving domains. The main idea of these methods is to incorporate the time evolution of the domain into the equations. However, the motion of the domain with respect to time induces convective fluxes in the resulting equations. These can lead to stability problems of the numerical method if they become ...
Dipartimento di Energetica “Sergio Stecco”, Università degli Studi di Firenze, Firenze, Italy
This paper presents and discusses the first phase results of a wide ranging project concerning the study and prediction of the efficiency and energy performances of natural ventilation systems existing inside historic buildings. The air flow patterns, air temperature and air velocity distribution inside a historic building in Florence, the Pitti Palace, were studied by a transient simulation. A ...
J. Torres, and D. Montane
Centre Huile Lourde Ouvert et Experimental (CHLOE), University of Pau, France
Department of Chemical Engineering, Virgili University, Tarragona, Spain
Steam Reforming of Ethanol using a Catalytic Wall Reactor (CWR) was successfully studied using COMSOL Multiphysics. A mathematical model was used to describe the reactor performance in terms of the main variables and dimensionless groups. Simulations showed that at specified conditions CWR maintains a thermal performance adequate for evaluating catalysts under a uniform temperature profile. CWR ...
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.
A. Auge, F. Wittbracht, A. Weddemann, and A. Hütten
Department of Physics, University of Bielefeld, Germany
Transport phenomena in spatially periodic magnetic systems, in particular the directed transport of magnetic beads in a so called magnetic ratchet (Brownian motor) are considered. Simulations are carried out to test and optimize this system, where the Smoluchowski equation with flux terms for the magnetic and gravitational force is used. Furthermore, experiments are carried out to verify the ...
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 ...
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 ...
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 ...
Dinex Emission Technology A/S, Middelfart, Denmark
Exhaust noise must meet legislation targets, customer expectations and cost reduction which call for design optimization of the exhaust systems in the design phase. One solution is to use 3 dimensional linear pressure acoustics and calculate the transfer matrix of the muffler. The transfer matrix is the basis for calculating either the insertion loss or transmission loss of a muffler. The 3D ...