Using COMSOL to Support a Cost-Effective, Non-Destructive Evaluation Approach for Predicting Bolt Failure in Highway Bridges
A. Elyea, B. Doubek, G. Hubbard, and D. Ozevin
Department of Civil Engineering
University of Illinois at Chicago
The development of a quantitative nondestructive evaluation method, as an alternative to visual inspection, for inspecting pre-tensioned bolts in fracture critical bridges is presented. In order to understand the ultrasonic behavior of a wide variety of bolt geometries used in bridges, numerical models of nine different bolt geometries were developed. The numerical models included the ...
A-S.Moreau, H.Lissek, and F. Bongard
Ecole Polytechnique Fédérale de Lausanne, Switzerland
JAST SA, Antenna Systems, Lausanne, Switzerland
In this context, a one-dimensional acoustic transmission line, exhibiting metamaterial properties, is presented. It is composed of an acoustic waveguide, periodically loaded with membranes having the function of series capacitances, as well as transversally connected open channels (denoted stubs) having the function of shunt inductances. A validation of the transmission line design is made with ...
S. Ni, C. Yang Koh, S. Kooi, and E. Thomas
Institute for Soldier Nanotechnologies
Dept. of Materials Science and Eng.
Recently, the concepts of fractal geometry have been introduced into electromagnetic and plasmonic metamaterials. With their self-similarity, structures based on fractal geometry should exhibit multi-band character with high Q factors due to the scaling law. However, there exist few studies of phononic metamaterials having fractal geometry. COMSOL is used to investigate vector elastic and ...
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 ...
Empirical Model Dedicated to the Sensitivity Study of Acoustic Hydrogen Gas Sensors Using COMSOL Multiphysics®
A. Ndieguene, I. Kerroum, F. Domingue, A. Reinhardt
Laboratoire des Microsystèmes et de Télécommunications/Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
Laboratoire d’Électronique et des Technologies de l’Information, CEA, LETI Grenoble, France
Due to the increasing demand for hydrogen gas sensors for applications such as automation, transportation, or environmental monitoring, the need for sensitive and reliable sensors with a short response time is increasing. This paper presents an empirical model that studies the sensitivity of acoustic hydrogen gas sensors. A parametric study based on the variation of physical properties of ...
R. Venegas, and O. Umnova
Acoustics Research Centre, University of Salford, Salford, United Kingdom
Granular materials have been conventionally used for acoustic treatment due to their sound absorptive and sound insulating characteristics. An emerging field is the study of acoustical properties of multi-scale porous materials. An example of these is a double-porosity granular material in which the grains are porous themselves. In this work, a computational methodology for modelling this type ...
SRM University & BITS Pilani University, Chennai, Tamil Nadu, India
Vibration analysis of perforated plates is extremely important when designing structures where resonance is the possible mode of failure. This paper deals with the vibration analysis of rectangular perforated plates with three different types of perforations. Vibration analysis is to be carried out by both COMSOL Multiphysics® Software and Experimental set-up. The applications of perforated ...
F. Botta, D. Dini, S. Gentili, G. Cerri
Dipartimento di Ingegneria Meccanica e Industriale, Università degli Studi di Roma Tre, Roma, Italy
Department of Mechanical Engineering, Imperial College London, London, United Kingdom
Turbomachines blades are forced by a load resulting from the interaction with the fluid. The consequent vibrations, and the associated fatigue phenomena, can give catastrophic failures and the reduction of the blades life. It could be increased if damping system are used. The piezoelectric materials has received considerable attention by many researcher for their potential application in the ...
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 ...
V.M. Acosta, E. Riera, G. Rodriguez, A. Pinto, A. Cardoni, J.A. Gallego-Juárez
Power Ultrasonics Group, CSIC, Serrano, Madrid, Spain
Pusonics, Arganda del Rey, Madrid, Spain
This work describes the design methodology and development of piezoelectric transducers for applications in fluids with COMSOL_Multiphysics. In these linear models for the acoustic-structure interaction approximate numerical solutions have been obtained. In order to perform the calculations, simplifications are only valid for low-power sound waves. Numerical modeling of piezoelectric transducers ...