D. Bichsel1, and P. Wittwer2
1HESSO, Ecole d'Ingénieurs de Genève, Geneva, Switzerland
2DPT, Université de Genève, Geneva, Switzerland
We discuss a new numerical scheme involving adaptive boundary conditions which allows to compute, at very low Reynolds numbers, drag and lift of airfoils with rough surfaces; efficiently and with great precision.As an example, we present the numerical implementation for an airfoil consisting of a line segment. The solution of the Navier-Stokes equations is singular at the leading and trailing ...
S. Palaich, and B. Daly
Physics and Astronomy Department, Vassar College, Poughkeepsie, NY, USA
When the dimensions of the material approach is a comparable size to the phonon mean free path, heat flow enters a new regime, the nanoscale. The Fourier and Cattaneo Equations describe bulk heat flow well, but radiative boundary terms must be considered when modeling nanoscale heat flow. We take these equations and input them into COMSOL with the hope of eventually linking nanoscale and bulk ...
COMSOL Grab Bag: How to Use a Versatile CFD Code to Model Interesting Problems from Cryogenic Storage to Biofuel Production
Senior Research Engineer,
NASA Glenn Research Center, Cleveland, OH, USA
Emily Nelson received her PhD in Mechanical Engineering from the University of California at Berkeley. She is a senior research engineer at NASA Glenn Research Center and specializes in the formulation and solution of problems in microgravity science, multiphase flow, porous media, risk analysis, and gravitational biology. This leads her to fundamental and applied approaches on a range of issues ...
M. Hackert, G. Meichsner, and A. Schubert[1,2]
Micromanufacturing Technology, Chemnitz University of Technology, Chemnitz, Germany
Fraunhofer Institute of Machine Tools and Forming Technology, Chemnitz, Germany
Electrochemical Machining with a closed electrolytic free jet is a special procedure to generate complex micro structures by help of anodic dissolution. The work piece shape is fabricated by supplying an electrolytic current through an electrolyte jet ejected from a small nozzle. In this study COMSOL Multiphysics is used to simulate the electric current density in the jet and the dissolution ...
SRI International, Menlo Park, CA, USA
Iouri Balachov is a Senior Scientist at SRI International (Menlo Park, CA) where he is leading development of Direct Carbon Fuel Cell technology for clean and efficient power generation from coal, biomass, and a wide variety of carbon containing fuels. Prior to SRI he was an engineer at Westinghouse nuclear (Pittsburgh, PA), researcher at Penn State University (State College, PA), and researcher ...
Capacitance Computation of Multilayered and Multiconductor Interconnects Using Finite Element Method
S. Musa, and M. Sadiku
College of Engineering, Prairie View A&M University, Prairie View, TX, USA
The development and analysis of interconnects in inhomogeneous structures such as very large scale integration chips, printed circuit boards, and multichip modules are essential for next-generation electronic products. In this paper, we illustrate fast and sufficiently accurate computation of capacitance matrices of multilayered and multiconductor interconnects applying the finite element ...
Numerical Analysis of the Impact of Geometric Shape Patterns on the Performance of Miniaturized Chromatography Systems
R. Winz, E. von Lieres, and W. Wiechert
Department of Simulation, University of Siegen, Siegen, Germany
Institute of Biotechnology, Research Centre Jülich, Siegen, Germany
We have implemented a two dimensional chromatography model for the analysis and optimization of structured micro pillar arrays. Dynamic surface interaction of solved molecules is taken into account by the kinetic Langmuir model. Variations of the pillar array geometry lead to deviations in the outlet concentration profiles. These deviations cannot be described by the one dimensional models that ...
Multiphysics Modeling of Engineered Structured Sorbents for the Adsorption of Carbon Dioxide and Water Vapor from Manned Spacecraft Atmospheres
NASA, Huntsville, AL, USA
In NASA’s Vision for Space Exploration, humans will once again travel beyond the confines of earth’s gravity, this time to remain there for extended periods. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. This paper describes efforts to improve on ...
L. Martinelli, and A. Lamberti
Universita di Bologna, Italy
Objective of this contribution is to show how to implement the Mild Slope Equations with COMSOL Multiphysics. These equations are commonly used to study the propagation of waves in harbors. Some interesting features are presented, namely the use of weak terms (used for the modelling of the source term); the evaluation of a smooth phase gradient from the complex dependent variable; a robust ...
Dept. of Mechanics and Machine Design, Research Centre on Choral and Instrumental Music (MUSICOS), University of Genoa, Italy
The paper attempts to give a contribution to the dynamic analysis of musical instruments. A multidisciplinary approach oriented to the study of mechanical, structural, vibratory and acoustical phenomena related to stringed instruments is discussed. The case study focused in this paper concerns the violins family: the geometry and the vibratory propagation of this instrument is very complicated to ...