Homogeneous and Inhomogeneous Model for Flow and Heat Transfer in Porous Materials as High Temperature Solar Air Receivers
O. Smirnova, T. Fend, P. Schwaryboezl, and D. Schoellgen
German Aerospace Center, Institute of Technical Thermodynamics, Koeln, Germany
Results of simulations on flow and heat transfer in a porous Silicon Carbide honeycomb structure applied as a solar air receiver are presented. In this application porous materials are put in concentrated solar radiation. Flux densities of up to 1000 MW/m² are reached. Simultanously, ambient air flows through the material to be heated up to temperatures of app. 800°C. This hot air is then used ...
A. Plana-Fattori[1,2], E. Chantoiseau[1,2], C. Doursat[1,2], and D. Flick[1,2]
AgroParisTech, Massy, France
INRA, Massy, France
Many liquid food processes involve coupled phenomena of fluid flow, heat transfer and product transformation. A typical example is the heat treatment of a starch suspension inside a tubular heat exchanger. Fluid flow influences heat transfer which determines temperature evolution along fluid trajectories. Temperature locally influences the food product transformation. The latter influences ...
Numerical Study of the Effect of Fins on the Natural Convection Driven Melting of Phase Change Material
C. Liu, and D. Groulx
Natural convection has to be accounted and simulated for in order to properly describe the physics encounter in the phase change process. A simplified two-dimensional model was created in COMSOL 4.1. Natural convection was accounted for by adding a volume force and using the Boussinesq approach. The heat transfer and laminar flow physics were used. Results showed that natural convection played ...
M. Fält, and R. Zevenhoven
Thermal and Flow Engineering Laboratory, Department of Chemical Engineering
Åbo Akademi University
Air-conditioning produced by traditional vapor compression cycle is an energy demanding operation. By using passive cooling methods is it possible to avoid, or at least reduce, the need for vapor compression cooling. A passive radiative cooling method could be a three windowed skylight, filled with a greenhouse gas. Earlier modeling of such a skylight has shown promising results, and work has ...
G. Tracanelli, M. Culos
Studio di Ingegneria Industriale Tracanelli, San Vito al Tagliamento, Italy
The energy pay back is one of the most interesting field especially in the steel industry where this contribution is strictly connected to steams and emissions inside and outside the plant. Perhaps, this application is sometimes disturbed by a strong variation of emissions (\"off gas\"). One example is the arc furnace where the process is very discontinuous and there are many fluctuations in the ...
R. Sikorski, T. Merrill
Rowan University, Glassboro, NJ, USA
Stroke is caused by an interruption of brain blood supply and is one of the leading causes of death and disability. A mild reduction of 2-5°C in tissue temperature through hypothermia has shown reduced tissue infarct size, increased tissue recovery, and positive neurological effects. This paper seeks to predict the outlet blood temperature in the common carotid bifurcation branches. In our ...
Using COMSOL to Estimate the Heat Losses of Composite Panels Undergoing Repairs Using Bayesian Inference
University of Washington, Seattle, WA, USA
Composite repairs involve applying a prescribed heat flux which must be adjusted to account for heat losses. These losses must be estimated. Parameter estimation requires a knowledge of sensitivities. This is often done using finite differences. As shown in the figure, substantial errors often occur. The paper describes the use of the PDE features of COMSOL to obtain much more accurate values by ...
COMSOL Multiphysics® Based Identification of Thermal Properties of Mesoporous Silicon by Pulsed Photothermal Method
N. Semmar, I. El Abdouni, A. Melhem
GREMI-UMR7344, CNRS/University of Orléans, Orléans, France
The silicon is mainly known under its single-crystal shape and polycrystalline. Since a few decades, a new type of morphology is developed: the porous silicon (p-Si). Meso-porous silicon (Mp-Si) is one of promising materials for future microelectronic chips multi-functionalization systems, and for micro-sensing devices. For thermal properties investigation many experimental systems were ...
G. Salazar Duarte, B. Schürer, C. Voss, D. Bathen
Linde AG, Munich, Germany
Universität Duisburg-Essen, Duisburg, Germany
Pressure Swing Adsorption (PSA) and Temperature Swing Adsorption (TSA) are commonly used for separation/purification of gas mixtures in industrial processes. The cycle time of industrial TSA processes usually ranges from several hours to days. The reason for this long cycle time is the usage of purge gas for heating and cooling the system (direct heating), which limits the application of TSA ...
Modelling of the Dynamical Fluorescent Micro-Thermal Imaging Experiment on the Heat Diffusion in the La5Ca9Cu24O41 Spin Ladder Compound
E. Khadikova, F. de Haan, P. H. M. van Loosdrecht
Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
Department of Physics, University of Cologne, Köln, Germany
The dynamical fluorescent micro-thermal imaging (FMI) experiment has been used to investigate the phonon-magnon interaction in the 1D Heisenberg antiferromagnet La5Ca9Cu24O41. This material shows highly anisotropic heat conductivity due to the efficient magnetic heat transport along the spin ladders in the compound carried by magnetic excitations (magnons). To extract information on the ...