Underground Coal Fire Extinction Model Using Coupled Reactive Heat and Mass Transfer Model in Porous Media
S. Suhendra, M. Schmidt, and U. Krause
Laboratory II.2: “Flammable Bulk Materials and Dusts, Solid Fuels”, Federal Institute for Materials Research and Testing (BAM), Berlin, Germany
Green house gases emission associated with natural hazard of underground coal seam fire has been recognized as a worldwide problem leading to global warming threat. Therefore, in this paper a model to study underground coal fire is presented and the results will be devoted to strategic development of coal fire extinction technology within the framework of Sino-German Coal Fire Research ...
Hyperbolic Heat Transfer Equation for Radiofrequency Heating: Comparison between Analytical and COMSOL Solutions
V. Romero-García, M. Trujillo, M.J. Rivera, J.A. López Molina, and E.J. Berjano
Centro de Tecnologías Físicas Acústica, Universidad Politécnica de Valencia, Valencia, Spain
Dpto. Matemática Aplicada, Instituto Universitario de Matemática Pura y Aplicada, Universidad Politécnica de Valencia, Valencia, Spain
Institute for Research and Innovation on Bioengineering, Universidad Politécnica de Valencia, Valencia, Spain
The Radiofrequency Heating (RFH) is widely employed to heat biological tissue in different surgical procedures. Most models analyze the RFH employing a Parabolic Heat Transfer Equation (PHTE) based on Fourier's theory. The PHTE can be used for problems involving long heating times or low thermal gradients. However, when the problem involves short heating times or extreme thermal gradients it is ...
A. Paoli, L. Seminara, D.D. Caviglia, A. Garibbo, and M. Valle
Department of Biophysical and Electronic Engineering, University of Genova, Genova, Italy
SELEX Communications S.p.A., Genova, Italy
Gas sensor arrays based on metal oxides operating at high temperature are commonly used in many application fields. They can operate on different principles and each sensor may show very different responses to the individual gases in the environment. Data coming from the array can be merged for reliable gas detection. One point which is common to the different sensors types is that the ...
M.H. Poech, M. Weiß, and K. Gruber
Fraunhofer Institute for Silicon Technology, Itzehoe, Germany
Since a couple of years, sintering becomes more and more important for power electronics. To press a semiconductor under high temperature in silver paste on a substrate promises benefits for durability. Tests with semiconductors of different thickness expose some problems. After the cool down, some of them fall slightly from the substrate. Stress in the boundary layer, caused by different ...
COMSOL Multiphysics® as a Tool to Increase Safety in the Handling of Acetylene Cylinders Involved in Fires
F. Ferrero, M. Beckmann-Kluge, and K. Holtappels
BAM Federal Institute for Materials Research and Testing Division II.1 “Gases, Gas Plants”, Berlin, Germany
In this paper a mathematical model for predicting the heating-up of an acetylene cylinder involved in a fire is presented. In the simulations polynomial functions were used to describe the temperature dependency of the thermal properties of the cylinder interior, which is a complex system composed by a solid porous material, a solvent and acetylene dissolved in it. Model equations covered heat ...
F. Pulvirenti, M. Aloisi, G. De Guidi, M. Mattia, and C. Monaco
Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania, Catania, Italy
Dipartimento di Scienze Geologiche, Università di Catania, Catania, Italy
Structural, morphological and ground deformation studies suggest that the eastern flank of Mt. Etna (eastern Sicily) is spreading seaward. Three contrasting models have been proposed: deep-seated spreading, shallow sliding and tectonic block movements. In order to better understand the kinematics of instability processes on eastern flank of Mt. Etna, a numerical simulation has been applied to a ...
Hydro-Mechanical Coupling in Saturated and Unsaturated Soils and its Consequences on the Electrical Behaviour
G. Della Vecchia, R. Cosentini, S. Foti, and G. Musso
DISTR, Politecnico di Torino, Torino, Italy
The consequences of hydromechanical coupling on the electrical conductivity of saturated and unsaturated soils are investigated experimentally and numerically. Simulations of the consolidation problem under vertical load for an elastic medium and of the coupled flow of two immiscible fluids have been performed in order to check the capability of electrical resistivity tomography to reconstruct ...
G. Megali, D. Pellicanò, M. Cacciola, F. Calarco, D. De Carlo, F. Laganà, and F.C. Morabito
DIMET Department, Faculty of Engineering, University “Mediterranea” of Reggio Calabria, Reggio Calabria, Italy
Constitutive properties of living cells are able to withstand physiological environment as well as mechanical stimuli occurring within and outside the body. We examined fluid flow and Neo-Hookean deformation related to the rolling effect. A mechanical model to describe the cellular adhesion with detachment is here proposed. We developed a finite element analysis, simulating blood cells attached ...
LASA Lab., Milan Dept., Istituto Nazionale di Fisica Nucleare, Milano, Italy
The understanding of quench, or the sudden transition to the normal state of a high-current Superconductor (SC), is fundamental for the design of a SC magnet, and it is widely discussed in the literature. This paper presents some simple COMSOL models, which are compared with well-known approximate formulae and some experimental results. These models allow a more precise description than it is ...
A. Gizzi, C. Cherubini, S. Migliori, and S. Filippi
Nonlinear Physics and Mathematical Modeling Lab, Engineering Faculty, University Campus Bio-Medico, Roma, Italy
International Center for Relativistic Astrophysics, University of Rome La Sapienza, Roma, Italy
Alberto Sordi Foundation, Research Institute on Aging, Roma, Italy
Postoperative or paralytic Ileus (PI) is a temporary aftermath of major abdominal surgeries. PI prevents the passage of food throughout the lumen leading to bloating, distension, emesis and pain. A plausible mathematical model for this phenomenology physiologically fine tuned including thermal variations, is presented here. Using COMSOL Multiphysics the existing intestinal ionic model have been ...