A.-M. Georgescu, S.-C. Georgescu
Hydraulics and Environmental Protection Department, Technical University of Civil Engineering, Bucharest, Romania
Hydraulics Department, University “Politehnica”, Bucharest, Romania
We propose a simplified numerical method to model the flow field downstream of an axial impeller. The method can be used for any axial hydraulic machinery for which, one is less interested by the flow between the blades, than by the flow field downstream of the machinery. The method is applied to an axial fan for which the pressure - flow rate curve is available. Numerical results are obtained ...
B. Chinè , M. Monno
Laboratorio MUSP, Macchine Utensili e Sistemi di Produzione, Piacenza, Italy
Politecnico di Milano, Dipartimento di Meccanica, Milano, Italy
Instituto Tecnologico de Costa Rica, Cartago, Costa Rica
Introduction: In metal foams production, nucleated gas bubbles expand in a heated metal in a mold, then the foam cool and solidify. Thereby energy, mass and momentum transfer mechanisms are present simultaneously in the system and must be taken into account. Metal foam (Figure 1) can be obtained by foaming a precursor, i.e. a mixing of aluminum (Al) powders with the blowing agent TiH2, placing it ...
S. Zhang, M. Pal, P. Barthelemy, M. Lei
Visualization Sciences Group, Burlington, MA, USA
Shell International Exploration and Production, Rijswijk, The Netherlands
The mass and recoverability of oil and gas in unconventional reservoirs strongly depend on the understanding the petrophysical properties of the rocks at a large range of scales. Three-dimensional imaging is capable of unveiling the detailed microstructures within the rocks down to the nanometer scale. Using a multiscale imaging protocol, a Devonian shale rock sample with heterogeneities is ...
A. Garcia, A. Marcus, F. Tejo, C. Precker, C. Moreira
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
Instituto Federal de Alagoas, Maceio, AL, Brazil
Piezoelectric buzzers are low cost devices which can be used successfully as actuators in diaphragm-based micro-pumps. The buzzers are piezoelectric wafers (lead-zirconate-titanate-PZT) that are glued on a brass membrane and they are available within different sizes and thicknesses. For the best performance of a diaphragm pump, it is necessary to have a large displacement of the membrane. This ...
A. Dobrinsky, M. Shatalov, M. Shur, R. Gaska
Sensor Electronic Technology, Columbia, SC, USA
Deep Ultraviolet Light Emitting Diodes (DUV LEDs) are presently operating at a relatively low efficiency, thus large amount of LED driving power is dissipating in heat. Thermal heating degrades LED performance and decreases LED’s lifetime. The degradation of DUV LED devices with temperature increase makes thermal management a key issue for DUV LEDs. We present a thermal analysis of DUV LED ...
R. Coker, J. Knox, K. Kittredge
NASA - Marshall Space Flight Center, Huntsville, AL, USA
All spacecraft systems must be minimized with respect to mass, power, and volume. Here, we focus on current efforts to improve system efficiency and reliability for water separation systems to be used on crewed vehicles. These development efforts combine sub-scale systems testing and multi-physics simulations to evaluate candidate approaches. The best performing options will then be ...
Andrew B. Randles
Julius M. Tsai
Institute of Microelectronics, Agency of Science, Technology, and Research, Singapore, Singapore
We have modeled surface acoustic wave (SAW) devices composed of piezoelectric materials: aluminum nitride (AlN), lithium niobate (LiNbO3), and quartz. These materials are often used in RF filters and wireless sensors, which require temperature compensation for stability. Using our COMSOL Multiphysics® simulation with published values of thermal expansion for each material, we simulated the TCF ...
K. K. Sriperumbudur, P. J. Koester, M. Stubbe, C. Tautorat, J. Held, W. Baumann, and J. Gimsa
 University of Rostock, Chair of Biophysics, Gertrudenstr. 11a, 18057 Rostock, Germany
 Microsystem Material Laboratory, Department of Microsystems Engineering (IMTEK), University of Freiburg, Germany
In spite of its low throughput, Patch-Clamp is the established method for intracellular measurements of the transmembrane potential. To address this problem, we have developed new biosensor-chips with micro-structured needle electrodes (MNEs). MNE-penetration of single cells growing on the MNE-tips leads to a situation comparable to the whole-cell mode in classical Patch Clamp. MNE-penetration ...
Modeling and Analysis of a Feedback-Controlled Active Magnetic Levitation System using COMSOL Multyphysics Finite Element Software
M. Nabi, and K. V. Ajeeth
Department of Electrical Engineering, Indian Institute of Technology Delhi, India
Magnetic levitation systems have been studied in the context of high-speed transportation as maglev trains, high speed machinery as magnetic bearings, and other similar engineering applications. In this paper, a three dimensional arbitrary shaped object is modeled and analyzed through COMSOL. Mechanically the levitated object has three degrees of freedom- two along the x and y axes and the third ...
P. Sharma, S. K. Dash, B. K. Nashine, S. S. Kumar, R. Veerasamy, B. Krishnakumar, P. Kalyanasundaram, and G. Vaidyanathan
 Fast Reactor Technology Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu
Sodium is used as a coolant in Fast Breeder Reactors. Eddy Current Flowmeter (ECFM) is used for measurement of sodium flow in the primary pump and at the outlet of the subassemblies. Eddy Current Flowmeter (ECFM) works on the principle of change in the magnetic field profile due to induced eddy currents as a result of sodium flow. It consists of a central primary winding, energized from an A.C. ...