S. Singer, W. H. Green
Massachusetts Institute of Technology, Cambridge, MA, USA
Transient, two-dimensional (axisymmetric) simulations of a cigarette subject to realistic static and forward smoldering cycles were performed. The computational domain consists of a porous packed bed of tobacco and a filter surrounded by a thin, porous paper and a region of surrounding air. The governing equations include overall mass conservation, momentum conservation, conservation equations ...
J. Schöne, A. Körnig, W. Beckert
Fraunhofer IKTS, Dresden, Germany
Reformer and catalytic burners are common components in fuel cell systems, crucial for efficient preparation of fuel and exhaust gases of the fuel cell stack. We intend to show the influence of radiation to the temperature distribution inside of a reformer unit. The model consists of an axisymmetric representation of the inlet-zone and a catalytic porous zone. Fluid flow, convective and ...
E. Licon, S. Casas, A. Alcaraz, J.L. Cortina, C. Valderrama
Universitat Politécnica de Catalunya, Barcelona, Spain
Ammonia separation from water by membrane contactor was simulated on transient state and compared with experimental data. Aqueous low concentrated solution of ammonium with high pH has been pumped inside the hydrophobic hollow fibers, acid solution in the outside part. The system is in closed loop configuration. In order to simulate the separation process, equations were developed considering ...
S. Gunsekaran , R. C. Thiagarajan
ATOA Scientific Technologies Private Limited, Bangalore, India
Multiphysics Simulations of Physico-chemical and Biological Treatment of wastewater is increasing due to the demand for cost efficient plant design and utilization. Among the many processes, a thorough understanding of the settling behavior of an activated granular sludge in the secondary settler of an Effluent Treatment Plant (ETP) is critical for the plant designers to determine the efficiency ...
N. Ghasem, M. Al-Marzouqi, N. Abdul Rahim
UAE University, Al-Ain, United Arab Emirates
A comprehensive mathematical model that includes mass and heat transfer was developed for the transport of gas mixture of carbon dioxide and methane through hollow fiber membrane (HFM) contactor. COMSOL Multiphysics® was used in solving the set of partial, ordinary and algebraic equations. The model was based on "non-wetted mode" in which the gas mixture filled the membrane pores for ...
The Effect of Electrolyte Flow Slots in Tooling Electrodes on Workpiece Surface Finish in Electrochemical Machining
Oregon State University, Corvallis, OR, USA
Electrochemical machining (ECM) uses electrolysis to precisely remove material at high rates. ECM has many advantages over conventional machining: no tool wear, no induced mechanical or thermal stresses, high removal rates virtually independent of material hardness or strength, and excellent surface finishes. However, challenges can arise during the design of the tooling electrode when ...
A. Malachowska, L. Pawlowski , A. Ambroziak , M. Winnicki , P. Sokolowski
University of Limoges, Limoges, France
Wroclaw University of Technology, Wroclaw, Poland
This paper studies oxide forming on titanium, during cold gas dynamic spraying with air. This is a quite new spraying method, which can be used to spray material having high affinity for oxygen. The model allows for the diffusion of oxygen through the oxide layer, reaction on the oxide-titanium interface and expansion of oxide, due to difference in molar density. It was implemented in COMSOL ...
Effects of Flow and Diffusion on Blood Coagulation in Platelet Poor Plasma: a Two-way Coupling Between Hemodynamics and Biochemistry
D. Magnabosco[1,2], H. van Ooijen, B. Bakker, R. van den Ham
Politecnico di Milano, Milan, Italy
Philips Research, Eindhoven, The Netherlands
Enzyme reactions, blood flow and diffusion in human vasculature play interacting and fundamental roles in blood coagulation. In this complex mechanism, the balance between blood and clot is a delicate equilibrium, whose tight regulation is vital to avoid pathologies such as bleeding and thrombosis. The secondary hemostasis triggered by tissue factor in platelet poor plasma is studied up to fibrin ...
Danish Technological Institute, Aarhus C, Denmark
The use of the finite element method for understanding and analyzing the freezing and drying processes of food products is in focus in this paper. The objective of this study is to develop a model that can predict temperature distribution and weight loss of food products during the freezing and drying processes. The problem was solved by utilizing heat, mass transfer and moving mesh model. In ...
H. Machrafi[1,2], S. Cavadias
University of Liège, Thermodynamics of Irreversible Phenomena, Liège, Belgium
University Pierre et Marie Curie, Laboratoire des Procédés Plasma et Traitement de Surface, Paris, France
The purpose of this work is to show whether an important difference in Lithium solid concentration and electrolyte concentration can be observed in a Lithium-ion battery model, when considering either the Butler-Volmer kinetics or the Tafel kinetics for describing the electrode kinetics (including a boundary layer between the electrolyte and the electrode particles). During discharge, the lithium ...