J.L.Wilson, and R. Dwivedi
New Mexico Institute of Mining and Technology, Socorro, New Mexico, USA
Geothermally driven natural convection in enclosures is a ubiquitous process occurring in many physical environments such as caves, mines, etc. We have numerically simulated laminar and turbulent natural convection in isolated air-filled cavities, buried in a more conductive rock mass. We have modeled heat transfer using COMSOL's Convection and Conduction mode. To better understand the convective ...
J. P. Caire, and A. Roure
LEPMI-ENSEE, Saint Martin d'Hères, France
The generation 4 of molten salt reactors using the thorium cycle are characterized by a temperature close to 1000 oC. The very large heat transfers involved between the reactor core and the external parts with minimal thermal losses are a major issue. This study investigated a possible inner loop made of a series of conventional graphite filter plate exchangers, pipes and pumps, using the COMSOL ...
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 the ...
S. Pietrzyk, and G.S. Yablonsky
Unité de Catalyse et Chimie du Solide, Université des Sciences et Technologies de Lille, France
Parks College, Saint Louis University, St. Louis, MO, USA
TAP (Temporary Analysis of Products) reactors are powerful instruments to study the kinetics of catalytic reactions. Their basic principle, exposition of evacuated solids of interest to narrow pulses containing very small amounts of gases, and measuring the concentrations of outgoing molecules permits to study practical catalysts under the conditions approaching those of molecular beam ...
Coupled Heat and Moisture Transfer in Building Components - Implementing WUFI® Approaches in COMSOL Multiphysics
B. Nusser, M. Teibinger
Holzforschung Austria, Vienna, Austria
Calculating time-dependent heat and moisture transports trough building components are important tasks in the area of building physics. A well known and worldwide used commercial software for this is WUFI®. From the scientific point of view the restricted access to governing equations is nevertheless a drawback of this software. In the present paper it is shown how the physical approaches used ...
A. Hallgarth, A. Zayer, A. Gatward, and J. Davies
Hazard Research & Risk Consultants Ltd, Aberystwyth, Wales, United Kingdom
Independent Consultants, United Kingdom
HazRes has developed a gas discharge and dispersion model in COMSOL which takes into account the effects of localized wind profiles and turbulence generated by buildings, structures and terrain on the dispersion of gases in question. The main focus of this work is to develop and provide clients with more accurate prediction methods relative to industrial standard software tools in modeling ...
Modeling the iodine removal efficiency and temperature behavior for an FADS charcoal filter by FEMLAB
Qin, Z.1, Wren, J.C.1, Moore, C.J.2
1 Department of Chemistry, The University of Western Ontario, London, Ontario, Canada
2 Chalk River Laboratories, Atomic Energy of Canada Limited Chalk River, Ontario, Canada
A key component of the Filtered Air Discharge System in nuclear power reactors is a charcoal filter, intended to remove gaseous fission products, mainly radioiodine, in the unlikely event of an accident. Models for removal of CH3I and temperature behaviour of a charcoal filter have been described. The CH3I removal model is based on a mass balance equation consisting of CH3I transport due to ...
G. Petrone, L. Cammarata, and G. Cammarata
Department of Industrial and Mechanical Engineering, University of Catania, Catania, Italy
Ventilation and Indoor Air Quality (IAQ) are issues of very high interest, determining comfortable conditions for occupants and no-contaminated local atmosphere. The aircraft cabins are more confined and have a higher occupant density than other indoor environments such as offices or residential houses. The passengers and the crew share a closed and ventilated cabin, which brings potential risk ...
Fundamental Three Dimensional Modeling and Parameter Estimation of a Diesel Oxidation Catalyst for Heavy Duty Trucks
A. Holmqvist and C.U.I. Odenbrand
Department of Chemical Engineering, Faculty of Engineering, LTH, Lund University, Lund, Sweden
Mathematical optimization can be used as a computational engine to generate the best solution for a given problem in a systematic and efficient way. In the context of monolithic converter systems, the parameter estimation problem (or inverse problem) is solved using Partial Differential Equations (PDE)-based models of the physical system coupled with an optimization algorithm. These problems are ...
Chinese Academy of Sciences, Dalian Institute of Chemical Physics, Beijing, China
We studied the transient characteristics of PEMFC and water transport during PEMFC start-up, concerning the following aspects: Effect of air stoichiometry change on transient behavior of PEMFC, Transient behavior of water transport during PEMFC start-up, and high temperature PEMFC modeling.