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 ...
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 ...
Naval Surface Warfare Center Crane Division, CRANE, IN, USA
A model of a horizontal atmospheric pressure chemical vapor deposition reactor was implemented to aid in the design of a laboratory based one. The model coupled momentum transport, energy transport, and mass transport phenomena to account for reacting fluid flow of a compressible gas in a heated chamber. The system modeled was silicon deposition from trichlorosilane in hydrogen carrier gas.
P. Goes, E. Hoferlin, and M. De Wulf
OCAS N.V. – ArcelorMittal Research Gent, Belgium
Finite element modelling of electrical machines usually assumes uniform magnetic properties and loss behaviour throughout the steel laminations. It is well known that manufacturing processes, like the assembly of the machine, deteriorate the properties of the core material. Generally, the measured iron losses in the machine are higher than the losses obtained under standard conditions. Taking ...
Study of Thermo-Electrical and Mechanical Coupling During Densification of a Polycrystalline Material Using COMSOL
F. Mechighel[1,2,3], B. Pateyron, M. El Ganaoui, and M. Kadja
CNRS SPCTS UMR 6638, Universite de Limoges, France
Département de Génie Mécanique, Universite de Annaba, Algerie
Département de Génie Mécanique, Universite de Constantine, Algerie
Spark Plasma Sintering (SPS) is a promising rapid consolidation technique that allows a better understanding and manipulation of sintering kinetics and therefore makes it possible to obtain polycrystalline materials (ceramic or metallic) with tailored microstructures. A numerical simulation of the electrical, thermal and mechanical coupling during SPS is performed. Equations for conservation for ...
A. Chanda, A.R. Choudhury, G. Ray, K. Dasgupta, and D. Nag
Jadavpur University, Kolkata, West Bengal, India
Atherosclerosis in arteries is caused by the formation of stenosis : fatty depositions, on the artery wall. In current medicine, the practice is to observe the maximum percentage occlusion at any arbitrary cross-section and diagnose the patient on that basis, which might not always present the real picture due to non-uniformity of the stenosis thickness. The present work attempts to simulate the ...
K. Suresh, B.V.M.P.S. Kumar, U.V. Kumar, M. Umapathy, and G. Uma
National Institute of Technology Tiruchirapalli, Tamil Nadu, India
A proximity DC current sensor using of a piezo sensed and actuated cantilever beam with a permanent magnet mounted at its free end is designed and simulated in COMSOL Multiphysics. The change in resonant frequency of cantilever is a measure of the current through the wire. The sensor is found to be linear with good sensitivity.
S.L. Firebaugh, E.A. Leckie, J.A. Piepmeier, and J.A. Burkhardt
United States Naval Academy, Annapolis, Maryland, USA
Microrobotics has promising applications in microsurgery and microassembly. A challenge in these systems is interfacing with the robot. This project explores crawling robots that are powered and controlled through a global mechanical vibration field. By controlling the frequencies present in the vibration field, the user can then steer the robot. The “robot” has a rectangular body with ...
S.M.F. Garcia, and P. Seshaiyer
U.S. Naval Academy, Annapolis, MD, USA
George Mason University, Fairfax, VA, USA
In this work we consider a 1-D mathematical model that describes a heating problem combined with electrical current flows in a body which may undergo a phase change as a result of the heat generated by the current, so-called Joule heating. The model consists of a system of nonlinear partial differential equations with quadratic growth in the gradient. Joule heating is generated by the resistance ...
Louisiana State University, Health Sciences Center, Shreveport, LA, USA
Steven Conrad received his MD degree from Louisiana State University in 1978, and his PhD degree in Biomedical Engineering from Case Western Reserve University in 1985. His clinical practice includes intensive care and emergency medicine, and his research interests include computational dynamics and bioinformatics. He has worked with dynamic models of gas transport in artificial lungs, and more ...