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 ...
A. Amardas , and S. Dwivedi
 Institute for Plasma Research, Gandhinagar, Gujarat, India
 COMSOL Multiphysics Pvt. Ltd, Bangalore, Karnataka , India
In this paper, detail magnetostructural analysis of fusion grade superconducting toroidal field coils that are used in ‘tokamaks’ is presented. The stresses that arise due to Lorentz forces in large size superconducting coils that carry high currents are of catastrophic type in nature. These stresses are expected to influence the integrated performance of the magnet system. In this ...
A. Eed Olamat, U. Hofmann, B. Pohl, and N. Nkemasong
University of Lübeck, Institute for Signal Processing, Lübeck, Germany
In order to investigate the implantation of microprobes into brain tissue, we developed a finite-element and a physical model to replace real biological tissue for mechanical testing. Penetrating forces of a tungsten indenter into a layered structure was investigated with different indentation speeds. Numerical and physical model are in good correspondence to each other and reproduce measured ...
J. Bouhattate, E. Legrand, A. Oudriss, S. Frappart, J. Creus, and X. Feaugas
Laboratoire d’Etude des Matériaux en Milieu Agressif, LEMMA, Bat. Marie Curie, La Rochelle, France
To understand a metal susceptibility to Hydrogen Embrittlement (HE), it is important to quantify the diffusion of hydrogen through a metallic membrane. Electrochemical permeation tests are the most common methods for experimentally determining the diffusion coefficient of a metal. However the parameters directly accessible from experiments are the time required for a stream to be observed and ...
Variable Capacitance And Pull-In Voltage Analysis Of Electrically Actuated Meander-Suspended Superconducting MEMS
N. AlCheikh, P. Xavier, J.M. Duchamp, C.H. Boucher, and K. Schuster
Institute of Microelectronics, Electromagnetism and Photonics (IMEP-LAHC), Minatec, Grenoble, France
Institute of Millimetric Radio Astronomy (IRAM), Grenoble, France
Variable capacitors between the fF and pF range are very interesting for high frequency applications like variable filters, resonators, etc. For radio astronomy applications variable capacitors, realized by electrostatically actuated, micromechanical Meanders-suspended bridges (MEMS) made of superconducting Niobium, have been measured to find C(V). A non plane capacitance behavior have been ...
S. Floody, R. Venegas, and F. Leighton
Universidad de Chile, Facultad de Artes, Departamento de Música y Sonología, Licenciatura en Sonido, Santiago, Chile
University of Salford, Acoustics Research Centre, Salford, UK
Universidad Tecnológica de Chile Inacap, Sede Pérez Rosales, Santiago, Chile
The present article presents a method to redistribute the acoustic modes of a rectangular enclosure in the low frequency range using slit resonators. The objective of the present work is to compare different strategies of optimal design in order to determine the dimensions of the resonators. The method of the finite elements will be used to model the acoustic physical behavior of the room. In ...
B. Boulbène, J. Morchain, and P. Schmitz
Université de Toulouse, NSA, UPS, INP, LISBP, Toulouse, France
We present numerical results involving microorganisms adhering to a plane surface submitted to a shear flow. The purpose is to have a better understanding of the removal mechanisms occurring during the cleaning in place of food processing equipments. The biological cell, i.e. the microorganism, is modelled as a rigid obstacle embedded in the bottom wall of the fluid domain. Shear induced ...
Aerodynamic Study For Air To Gas Leakage Reduction In A Typical Rotary Regenerative Air Preheater Of Coal-Fired Steam Generators
L. Ferravante, C. Zagano, and V. Marra
RSE S.p.A. - via Rubattino, Milano, Italy
COMSOL S.r.l. - Via Vittorio Emanuele II, Brescia, Italy
The present study relates to the reduction of the amount of air to gas leakage in a typical rotary regenerative air preheater of coal-fired steam generators, by means of computational thermo-fluid-dynamics. Due to the gaps, or clearances, required for rotation, there is a significant amount of leakage of the higher pressure air to the lower pressure gas stream. This paper presents a turbulent ...
A. Bradji, E. Holzbecher, and M.S. Litz
Department of Mathematics, University of Annaba, Algeria
Georg-August Universität Göttingen, Germany
It is well known that the convergence rate of a numerical model is significantly reduced, when the genuine character of the setting with differential equation and boundary condition is not given anymore. Here we examine the decrease of convergence order for models using COMSOL in which the problem set-up includes a coupling between a 1D and a 2D subdomain. In terms of physics we are dealing with ...
J. Plawsky, W. Gill, M. Riley, J. Borja, and B. Williams
Rensselaer Polytechnic Institute, Troy, NY, USA
Understanding and predicting the reliability of new generations of high and low-k dielectrics is increasingly important for gate oxides and interlayer dielectrics as both films have become thinner and scaling of device operating voltages has not kept pace with the decrease in the size of the dielectrics. We have developed a series of COMSOL-based mass transfer-based models that have proven to ...