Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

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[2], B. Bakker[2], R. van den Ham[2]
[1]Politecnico di Milano, Milan, Italy
[2]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 ...

Analyte Capture from Liquid Samples: Size Matters

M. Weber[1], M. Reed[1]
[1]Yale University, New Haven, CT, USA

Arrays of vertical pillars, Micro Purification Chips, have been widely used for analyte capture from liquid samples [Henderson et. al, 2006], [Toner et. al, 2007], [Stern et. al, 2010]. However exact understanding of the capture efficiency mechanisms has not been previously explained. Here we present a model in COMSOL Multiphysics® which calculates analyte capture efficiency based on initial ...

Study of Electrochemically Generated Two-Phase Flows

J. Schillings [1], O. Doche [2], J. Deseure [1],
[1] LEPMI, Grenoble, France
[2] SIMAP, Grenoble, France

The dependency of electrochemical processes performances on mass transfer is well-known. Electrolyte flow in the vicinity of electrodes surface can enhance reactions due to increased mass transfer. This flow can be generated by the production of a gaseous phase, leading to a natural bubble-driven convection flow. As a drawback, gas bubbles also modify electrodes active surface and the ...

Numerical Modeling of the Original and Advanced TEMKIN Reactor for Catalysis Experiments in Laboratory Scale - new

D. Götz[1], M. Kuhn[1], P. Claus[1]
[1]Ernst-Berl-Institute/Chemical Technology II, Darmstadt, Germany

Many industrial, especially heterogeneously catalysed, processes are characterised by a strong interaction between the reaction kinetics and transport phenomena. Because experiments in laboratory scale can be very time- and cost-intensive, Temkin and Kul’kova developed a new reactor design for the direct testing of industrial catalysts. Based on this concept of linearly alternating catalyst and ...

Pseudo-3D Multiphysics Simulation of a Hydride Vapor Phase Epitaxy Reactor

M. Hackert-Oschätzchen[1], M. Penzel[1], P. Plänitz[2], A. Schubert[1][3]
[1]Chemnitz University of Technology, Chemnitz, Germany
[2]GWT-TUD, Dresden, Germany
[3]Fraunhofer Institute for Machine Tools and Forming Technology IWU, Chemnitz, Germany

Gallium nitride (GaN) and its related nitride alloys with special physical properties are in technical areas of high interest. The growing of gallium nitride boules on non-native sapphire or silicon carbide requires complicated mechanisms of defect reduction in the lattice structure. Thus the production of gallium nitride substrates is a challenge. Hydride Vapor Phase Epitaxy (HVPE) is a ...

Turbulent Compressible Flow in a Slender Tube

K.O. Lund[1], C.M. Lord[2]
[1]Kurt Lund Consulting, Del Mar, CA, USA
[2]Lord Engineering Corp., Encinitas, CA, USA

Pressure-drop experiments were conducted for the turbulent, compressible flow of air in a small, slender tube, and modeled with COMSOL heat transfer module, and analytically. A scalar integration variable is introduced which integrates the mass velocity [kg/m²s] over the inlet area and iteratively equates this to the input mass flow [kg/s]. For computation, the temperature specification is ...

Experimental Validation of Model of Electro-Chemical-Mechanical Planarization (ECMP) of Copper

J. Ebert[1], S. Ghosal[1], A. Emami-Naeini[1]
[1]SC Solutions, Sunnyvale, CA, USA

This paper describes the development of a COMSOL model of Electro-Chemical-Mechanical Planarization (ECMP) that was validated with experimental data. ECMP is used for processing of semiconductor wafers. We developed a 2D model of flow of phosphoric acid solution (the electrolyte) between two parallel plates that focuses on the physics and electrochemistry in ECMP. The model includes steady-state ...

Multi-Dimensional Adsorption Model of CO2/H2O Sorbent Bed

C. Gomez [1], R. F. Coker [1], J. Knox [1], G. Schunk [1]
[1] NASA MSFC, Huntsville, AL, USA

The primary interest of the VC (Vacuum Characterization) test is to experimentally characterize the adsorption and vacuum desorption of CO2 and water vapor of a pelletized sorbent bed in a large diameter column. The VC test article is shown in Figures 1 and 2. The aluminum canister is 3” in diameter and approximately 8” long allowing for variable sorbent bed loads from 1” to 6” in length. A ...

Ultrasound-assisted Microfluidic Devices: Insights and Optimization of Sono-microreactors

F. J. Navarro-Brull [1], P. Poveda [2], J. Ramis [2], R. Gómez [1],
[1] Departament de Química Física, Universidad de Alicante, Alicante, Spain
[2] Departament de Física, Enginyeria de Sistemes i Teoria del Senyal, Universidad de Alicante, Alicante, Spain

Possible drawbacks of microreactors are inefficient reactant mixing due to the predominance of laminar flow and clogging (when solid-forming reactions are performed or solid catalyst suspensions are used). Ultrasound has been successfully implemented not only to prevent these problems but also for its well-known mixing and particle-dispersion effects. Several configurations have been used for ...

Chemical Reactions at Interfaces During Droplet Formation in Microchannels

Simeon Cavadias [1], Cédric Guyon [2], Gerrardo Vera De la Cruz [3],
[1] Institut Pierre-Gilles de Gennes (IPGG) - UPMC, France
[2] Chimie-ParisTech - Institut Pierre-Gilles de Gennes (IPGG) , France
[3] Master Nuclear Energy, ISTN (Saclay), France

Emulsions, small liquid droplets of oil in water or water in oil, find wide application in, pharmaceutical products, fine chemicals, analytical chemistry. Microfluidic devices allow creation of uniform droplets with a tight distribution. The COMSOL Multiphysics® software model presented here is an extension of the tutorial “Droplet Breakup in a T- junction”. In this tutorial uniform droplets ...