V. S. Nagaraja, Ramanuja H. S., Deepak K, S. L. Pinjare
Electronics and Communication Engineering, Nitte Meenakshi Institute of Technology, Bangalore, Karnataka, India
In this work, a MEMS based condenser microphone [1,2] using Polyimide as the diaphragm has been designed. The microphone structure has a backplate placed on top of the diaphragm. The backplate and the diaphragm are made up of polyimide. The two polyimide plates are separated by air gap which is achieved by using Aluminium as a sacrificial layer in between, which is etched away to create the air ...
Blondel, P., Girardin, G.
AREVA, Centre Technique Framatome ANP, Dpt Corrosion-Chimie Porte Magenta, Le Creusot France
The modelling of the incorporation of non-volatile solutes from liquid coolant into porous crud deposited on a heating surface under subcooled boiling conditions has been investigated. A suitable model for the concentration of solutes in porous deposits with steam chimneys, proposed by Pan et al., has been studied and implemented with the FEMLAB® software. With this model, the porous ...
London School of Economics
In this presentation we study a PZT Distributed Mode Actuator. In particular, we cover the modeling strategy, the governing equations, modeling setup, the solution and validation. The presentation also gives a comparison between the usage of different Numerical Methods for solving the Partial Differential Equations for this particular type of ...
S. Kiravittaya, P. Cendula, A. Rastelli, and O. Schmidt
Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany
Institute for Integrative Nanosciences, Dresden, Germany
Strain induced by local deformation of a flexible micrometer-sized semiconductor tube is quantified by modeling a ball pressing on the tube wall. By changing the pressing condition, we are able to change the strain state of the tube wall incorporating self-assembled quantum dots (QDs) in the wall. The QD emission energy is calculated in COMSOL® by solving the Schrödinger wave equation ...
Kurt Lund Consulting, Del Mar, CA , USA
The present work formulates the dynamics of a slender structure as a long beam. This results in a PDE that is fourth-order in space, and second order in time. In COMSOL the coupling method is used to decompose this problem into two second-order equations, one for displacements, and one for bending moments, which are then solved to obtain frequencies and mode shapes. For verification of ...
R. Malek-Madani, and J.J. Radice
US Naval Academy, Annapolis, MD, USA
The study of deformation of an adhesively bonded sandwich structure reduces to solving the biharmonic equation for the Airy Stress subject to mixed boundary conditions. Because of the nature of the boundary conditions, this boundary value problem does not yield to the standard elementary methods and must be attacked by numerical methods. In this paper we will use COMSOL\'s capability in two ways ...
Y.F. Wang, Y.S. Wang, L. Wang
Institute of Engineering Mechanics, Beijing Jiaotong University, Beijing, China
Department of Mechanical Engineering, Østfold University College, Halden, Norway
We show in this paper that by careful design of the geometry of the resonators, complete bandgap with relatively low center frequency can be obtained for 2D and 3D Phononic Crystals with resonators. The generation of the bandgap is due to the local resonance of the unit cell. Spring-mass and spring-pendulum models are developed to predict the boundaries of the complete bandgap. The predicted ...
M. Quinn, D. Whitlow, O.D.S. Taylor, M.H. McKenna
 Engineer Resource and Development Center, United States Army Corps of Engineers, Vicksburg, MS, USA
Bridge piers and abutments makeup the bridge substructure and transmit loads from the superstructure to the bridge foundation material (Figure 1). The bridge abutment serves three purposes: to provide vertical support to the bridge superstructure where the bridge ends, to connect the bridge with the approach roadway, and to retain roadway base materials. There are several types of abutment ...
M. Ding, J. Lin
MIT/WHOI Joint Program in Oceanography, Cambridge, MA, USA
Woods Hole Oceanographic Institution, Woods Hole, MA, USA
We used COMSOL Multiphysics 4.3 to simulate the 2D elastoplastic deformation and plastic strain in a wedge-shaped plate above a subducting interface. The modeling results reveal that a pair of conjugate normal faults would first appear in the thinner part of the plate. Subsequently, a second pair of conjugate thrust faults would form in the thicker part of the plate. The duration of the seamount ...
Multiphysics Modeling and Simulation of MEMS based Variometer for Detecting the Vertical Speed of Aircraft in Avionics Applications
K. Umapathi, K. Sukirtha, C. Sujitha, K. A. Noushad, Venkateswaran, R. Poornima, R. Yogeswari
United Institute of Technology, Coimbatore, Tamil Nadu, India
Sri Krishna College of Engineering and Technology, Coimbatore, Tamil Nadu, India
The objective of this work is to develop a MEMS based Variometer to measure the vertical speed and to sense the instantaneous rate of climb or descent in Aircrafts to meet the miniaturization requirements in avionics industry. The design consists of dielectric material in between two micro electrodes. The micro diaphragm is placed on one of the electrode. As the aircraft changes altitude, the ...