Simulations of Scanning Electrochemical Microscopy Experiments in Pure Negative and Positive Feedback Mode with Ring Microelectrodes
J. Mauzeroll, M. Mayoral, and D. Fabre
Department of Chemistry, Université du Québec à Montréal, Montreal, Quebec, Canada
Scanning electrochemical microscopy (SECM) is a powerful tool recently developed for studying structures and processes in micrometer and submicrometer sized systems. It can probe electron, ion, and molecule transfers, and other reactions at solid-liquid, and liquid-liquid, interfaces . This versatility allows for the investigation of a wide variety of processes, from metal corrosion to ...
Effect of Bed Diffusion and Operating Parameters on Char Combustion in the Context of Underground Coal Gasification
S. Mahajani, and G. Samdani
Indian Institute of Technology Bombay
Char combustion is one of the most important reactions in the process of Underground Coal Gasification (UCG). Experiments are performed in a boat reactor under near isothermal condition to demonstrate effects of heat and mass transfer and bed diffusion through ash layer. To obtain a complete overview of boat experiments and to further get insights, CFD analysis of boat reactor is performed using ...
S. Pramanik, G. L. Kulukuru, M. Mishra
Indian Institute of Technology Ropar, Rupnagar, Punjab, India
When a less viscous fluid displaces a more viscous one in a porous medium or Hele-Shaw cell, the interface between the two miscible fluids does not remain flat and deforms into fingers growing in time . It occurs due to the faster movement of less viscous fluid than the more viscous one, for a given pressure gradient. Fingering affects in aquifers, in packed bed reactors, and detrimental to ...
C. Wylock, S. Goffin, M. Aubinet, B. Longdoz, B. Haut
Université Libre de Bruxelles (ULB), Transfers, Interfaces and Processes (TIPs), Brussels, Belgium
University of Liège-Gembloux Agro-Bio Tech, Unit of Biosystem Physics, Gembloux, Belgium
INRA, Centre INRA de Nancy, UMR1137 Ecologie et Ecophysiologie Forestières, Champenoux, France
The assessment of forest soil respiration and its isotopic composition is one of the important issues for the carbon cycling modeling (greenhouse gas emission control) because it is often inaccurate. Soil respiration is a complex process, depending on the coupling of several phenomena, which is therefore highly sensitive to any disturbance. In this work, the dynamics of the transport of two ...
I. Borsi and A. Fasano
Dipartimento di Matematica U. Dini, Università di Firenze, Firenze, Italy
In this paper we present a model to describe the process of waste water filtration based on hollow-fibre membrane filters. In particular, we deal with membranes whose pores diameter is in the range 0.01-0.1 µm. The main problem in these filtering systems is the membrane fouling. The mathematical model consists in two equations for the Darcy's flow through the filter, coupled with an ...
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 ...
B. Bunner , A. Kromidas , M. Kele , and U. Neue
Waters Corp, Milford, MA, USA
High-Performance Liquid Chromatography (HPLC) is a standard method in the pharmaceutical industry for the separation and identification of chemical compounds. Modeling of band transport, or band broadening phenomena, can provide tremendous insight into problems of chromatography that are difficult or impossible to measure experimentally. We used COMSOL to analyze two classes of problems in ...
H. Ishimori, K. Endo, H. Sakanakura, M. Yamada, M. Osako
Ritsumeikan University, Kusatsu, Shiga, Japan
National Institute for Environmental Studies, Tsukuba, Ibaraki Prefecture, Japan
This paper presents the numerical simulation model for radiocesium leaching and transporting behavior in municipal solid waste (MSW) landfill and discusses on the design for the required geometry and properties of the impermeable final cover and the soil sorption layer, which work for containment of hazardous waste such as radiocesium-contaminated MSW generated by Fukushima Daiichi nuclear ...
Optimization of the Herringbone Type Micromixer Using Numerical Modelling and Validation by Measurements - new
E. Tóth, K. Iván, P. Fürjes
Pázmány Péter Catholic University, Budapest, Hungary
Research Centre for Natural Sciences Institute for Technical Physics and Materials Science Hungarian Academy of Sciences, Budapest, Hungary
COMSOL Multiphysics® software was used in this study to simulate mixing by diffusion and by secondary flow. Particle tracing model was applied to simulate the mixing of cells in the microchannel. Results agreed well with the measurement, an optimal herring-bone structure was proposed for integration into a bioanalytical system.
B. Courcelles , C. Raymond-Poirier ,
 École Polytechnique de Montréal, Montréal, QC, Canada
In the context of increasing demographic pressures around the world, soil improvement techniques constitute viable alternatives to expensive foundations. Among these techniques, the biocalcification of granular soils appears as a promising alternative relying on the formation of calcium carbonates. The process is relatively basic and energy efficient, as based on the metabolic activity of the ...