Ricklefs, U., Luo, H.
FH Giessen-Friedberg, FB EI
Mit FEMLAB 2.x und 3.1 wurden Voruntersuchungen zu zwei Anwendungen versucht. Im ersten Projekt sollte die Möglichkeit geklärt werden, FEMLAB für die Verhaltenssimulation integrierter ASIC-Photodioden einzusetzen und in der zweiten Anwendung sollten spezielle photonische Kristalle untersucht werden.
Institut für Geoökologie der Technischen Universität, Braunschweig
Kontinuierliche populationsdynamische Modelle lassen sich durch Systeme von gewöhnlichen Differentialgleichungen darstellen. Die räumliche Ausbreitung wird durch parabolische partielle Differentialgleichungen beschrieben, im einfachsten Fall durch eine Konvektions-Dispersionsgleichung. Für gekoppelte Populationen erhält man damit ein System von Reaktions-Diffusionsgleichungen mit erheblichen ...
Computations on the coupled heat and mass transfer during fires in bulk materials, coal deposits and waste dumps
Krause, U., Schmidt, M., Lohrer, C.
Federal Institute for Materials Research and Testing (BAM), Division II.2 “Reactive Substances and systems”, Berlin, Germany
In porous combustible matter low-rate oxidation takes place at ambient conditions. In large stockpiles of bulk goods, coal heaps, waste dumps etc. it may occur that the heat released by the oxidation reaction is not fully transmitted to the surroundings but raises the temperature within the deposit. This triggers a positive feed-back loop since the oxidation rate increases with temperature. The ...
A multiphysics approach of the styrene free radical polymerization modeling performed in different microreactors
Serra, C., Sary, N., Schlatter, G.
LIPHT-CNRS UMR 7165, ECPM-ULP Strasbourg
This paper investigates the modeling of styrene free radical polymerization in two different types of microreactor for which the wall temperature is kept constant. The simulations are performed with the help of FEMLAB 3.1 to solve simultaneously partial differential equations resulting from the hydrodynamics, thermal and mass transfer (convection, diffusion and chemical reaction). The ...
Defining the stress fields for the safety design of the LBT adaptive secondary mirror - FEMLAB/MATLAB set of functions to define and compute shell overstressing
Del Vecchio C., Busoni L., Riccardi, A.
This paper presents the most important safety issues of the thin glass shell of the LBT Adaptive Secondary Mirror. Two overstressing conditions are investigated: the condition in which the mirror shell is passively supported and the condition of a failure of the control system governing the actuator forces. The two stress analyses determine the portion of the mirror which may exceed a certain ...
Tim Cale, Daniel Bentz, and Max Bloomfield, RPI
We discuss the use of 3D grain continuum modeling to study grain boundary migration driven by differences in strain energy density. COMSOL Multiphysics is used to compute stresses and strain energy densities in polycrystalline structures caused by temperature changes. We treat each grain as a single crystal, with the anisotropic elastic properties of single crystal Cu appropriately rotated to ...
G. Bonmassar, and A. Golby
AA. Martinos Center, Massachusetts General Hospital, Charlestown, Massachusetts, USA
Department of Neurosurgery, Brigham and Women’s Hospital, Boston, Massachusetts, USA
A new type of MRI compatible intracranial electrode based on Polymer Thick Film (PTF) is presented and studied using COMSOL Multiphysics. The geometry considered was a two-dimensional cross section cut of 5 mm thick electrodes with 5 cm leads on top of a 2×10 cm slab representing Gelfilm, or the substrate. The resistive leads were compared with metallic leads to estimate the ...
Variation of the Frost Boundary below Road and Railway Embankments in Permafrost Regions in Response to Solar Irradiation and Winds
N.I. Kömle and W. Feng
Space Research Institute, Austrian Academy of Sciences, Graz, Austria
State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Lanzhou, China
We present COMSOL solutions for a coupled gas flow and heat transfer problem, which occurs particularly when traffic pathways are constructed in high altitude and arctic regions, where the underground is frozen soil. To avoid melting of the frozen ground (which usually leads to mechanical instability) one has to find suitable measures to keep the subsurface soil and the embankment suitably cool. ...
Minhee Jun, and Jason V. Clark
Departments of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, USA
Large deflection actuators are becoming increasingly important for microsystems. Since actuation forces are usually small, large deflection actuators usually require flexures with low stiffness. Rectangular serpentine flexures are often used for such actuators due to their low stiffness and large linear deflection range. In this paper we investigate the performance of curved serpentine flexures ...
A. Pors, O. Albrektsen, S.I. Bozhevolnyi, and M. Willatzen
Mads Clausen Institute, University of Southern Denmark, Sønderborg, Denmark
Institute of Sensors, Signals and Electrotechnics, University of Southern Denmark, Odense, Denmark
The use of plasmonic effects to dramatically enhance the electromagnetic field near the surface of a metallic nanostructured surface has grown into a large research area in the effort to take advantage of the surface enhanced field. In this paper the electromagnetic field near a nano-sized truncated spherical cavity embedded in a gold substrate is investigated and modeled in 3D with COMSOL ...