P. Buttin, B. Malki, P. Barberis, and B. Baroux
SIMAP/groupe SIR, CNRS, France
AREVA - AREVA NP - CEZUS Research Center, France
This paper studies multicomponent transport through zirconia, assuming a chemical reaction involving electrons and oxygen vacancies defects. Classically, according to the Wagner theory for ambipolar diffusion, the electroneutrality condition in the oxide is considered. Therefore three constraints must be satisfied on the transport problem: oxide stoichiometry, electroneutrality and the source ...
A. Melas, A.G. Konstandopoulos, L. Isella, Y. Drossinos
Department of Chemical Engineering, Aristotle University, Thessaloniki, Greece
European Commission, DG Energy, Luxemburg
European Commission, Joint Research Centre, Ispra, Italy
Aerosol and colloid aggregates are complex fractal-like structures composed of primary spheres. The drag force exerted on a fractal-like object is usually determined by solving numerically the Stokes equation. In this study we calculate it by relating it to a molecule-aggregate collision rate. We create the fractal aggregates with a cluster-cluster aggregation algorithm using the software ...
S. Sandoval Torres, E. Hernández-Bautista, J. Rodríguez-Ramírez, A. Carrillo Parra
Instituto Politécnico Nacional, CIIDIR, Oaxaca, Mexico
Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León, Linares, N.L. México
In this work, the numerical simulation of Mexican softwood (Pinus pesudostrobus) drying is presented by solving a physics-based model. The model was developed by considering the heat and mass transport and the representative elementary volume, which involves the solid, liquid and gas phases. We solved a system of partial differential equations by numerical factorization in COMSOL Multiphysics ...
D. Baldissin and D. Lombardo
Compumat S.r.l., Torino, Italy
A two-dimensional mathematical model for the absorption and desorption of H2 in LaNi4.8Al0.2 was developed and experimentally validated. The model is composed of an energy balance, a mass balance and a momentum balance. These differential equations are numerically solved by means of the finite element method using the software COMSOL Multiphysics®. From a comparison between theoretical ...
Analysis of Superheater Tubes with Mutual Irradiation as Applied to a Solar Receiver Steam Generator
N. Lemcoff, S. Wyatt
Rensselaer Polytechnic Institute, Hartford, CT, USA
Alstom Power, Windsor, CT, USA
The objective of this paper is to analyze the temperature variations within a superheater tube of a solar receiver steam generator. The tube is heated by concentrated, collimated solar irradiation with major cooling by an internal steam flow. The influence of heat loss by radiation, internal convection, and conduction are considered. Analytical models are obtained for an isolated tube, and the ...
C. Wylock, A. Rednikov, B. Haut, P. Colinet
Université Libre de Bruxelles (ULB), Transfers, Interfaces and Processes (TIPs), Brussels, Belgium
This work deals with the modeling and the numerical simulation of the CO2 absorption, coupled with a chemical reaction, in an initially quiescent aqueous solution of sodium carbonate (Na2CO3) and bicarbonate (NaHCO3), inside a Hele-Shaw cell. In our Hele-Shaw cell, the liquid fills partially the gap between two parallel transparent Plexiglas plates. CO2 is forced to flow above the liquid in the ...
Simulations of Heat and Mass Transport During Biomass Conversion Processes Using 3D Biomass Particle Models with Realistic Morphology and Resolved Microstructure - new
P. Ciesielski, M. Crowley, L. Thompson, B. Donohoe, D. Robichaud, A. Sanders, M. Nimlos, T. Foust
Biosciences Center, National Renewable Energy Laboratory, Golden, CO, USA
National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, USA
Quantum Electronics & Photonics Division, National Institute of Standards & Technology, Boulder, CO, USA
Predictive simulations of biomass conversion processes will improve their technical performance and reduce economic uncertainty surrounding industrialization of biofuels production. The majority of present conversion simulations treat the biomass feedstock with simplifying assumptions that neglect important characteristics that are unique to biomass particles. These characteristics, including ...
A. Freni, and F. Cipiti
CNR- Institute for Advanced Energy Technologies “Nicola Giordano”, Messina, Italy
In this paper, a 3D dynamic simulation for a portion of a metal hydride-based (LaNi5) hydrogen storage tank is presented. The model is based on heat and mass balances and considers coupled heat and mass transfer resistance through a non-uniform pressure and temperature sorbent bed. The governing equations were implemented and solved using the COMSOL Multiphysics software package. The simulation ...
K. Kannappan, G. Bogle, J. Travas-Sejdic, and D.E. Williams
University of Auckland, Auckland, New Zealand
Electrochemically-active conducting polymers (ECP) swell or shrink in response to ion and solvent incorporation or ejection as a result of electrochemical reaction of the polymer. When anodic potential is applied to an electrode attached to one end of ECP strip, the oxidation process starts from the electrode and proceeds along the polymer, propagating as a wave. This wave is driven as a ...
Experimental and Numerical Study of Microbial Improved Oil Recovery in a Pore Scale Model by using COMSOL
M. Shabani Afrapoli, L. Shidong, S. Alipour , and O. Torsaeter
Department of Petroleum Engineering and Applied Geophysics
A number of visualization experiments are carried out at the laboratory temperature with oil, brine and bacteria suspension for evaluating the performance of MIOR in a glass micromodel. The observations show the effects of bacteria on remaining oil saturation. The interfacial tension reduction, wettability alteration and flow pattern changes are recognized as active mechanisms. COMSOL ...