ÅF, Stockholm, Sweden
In this paper a pre-study on using COMSOL Multiphysics for rotordynamic analysis is presented. It is concluded that it is possible to use COMSOL Multiphysics to perform rotordynamical analysis. However, there are no standard environment for rotordynamics, hence the user has to extend the structural model with the rotordynamics effect such as gyroscopic effect and rotordynamical coefficients. By ...
Multiphysics Modelling of Sound Absorption in Rigid Porous Media Based on Periodic Representations of Their Microstructural Geometry
Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
Sound absorption in porous materials with rigid frame and open porosity can be very effectively estimated by applying the Johnson-Allard model in order to substitute a porous medium with an equivalent effective fluid and then utilise the Helmholtz equation for time-harmonic acoustics. The model uses several parameters which characterize the micro-geometry of porous material from the macroscopic ...
Surface Acoustic Wave Scattering Matrix Evaluation Using COMSOL Multiphysics®: Application to Surface Acoustic Wave Transmission Through 2D Surface Phononic Crystal
S. Yankin[1,2], A. Talbi, V. Preobrazhensky[1,3], P. Pernod, O. Bou Matar, A. Pavlova
 Joint International Laboratory LICS/LEMAC, IEMN UMR CNRS 8520, EC Lille, Villeneuve d'Ascq, France
 Saratov State University, Saratov, Russia
 Wave Research Center, Russian Academy of Sciences, Moscow, Russia
This contribution is dedicated to numerical analysis of SAW propagation though 2D surface phononic crystal (PnC) and FE method is nowadays one of most common tool for such calculation. The device under investigation consists of two dispersive IDT and lattice of ferromagnetic pillars realized on 128°YX LiNbO3. In addition to dispersion curves calculations this work describes the results of ...
M. Yeoman, V. Sivasailam, A. Tomar
Continuum Blue Ltd., Ystrad Mynach, UK
Jaguar Land Rover Ltd, Coventry, UK
The design of windows and or other perforated structures which allow the free flow of air into & out of a building or system, while being fully soundproofed or attenuate certain frequencies is of great interest to architects and design engineers, where sound as a longitudinal wave, is difficult to separate it from its medium of propagation. In this work, we present the analysis of air ...
Study & Modeling of 'Acoustic Matching Layers' for Ultrasound Imaging Probes Through Pulse-Echo FEM Simulation - new
Esaote SpA, Florence, Italy
Ultrasound Imaging probes are specific devices that require a very detailed design of acoustic impedance match for the stack of layers that form the probe head (1,3). These are typically made of silicone rubber, special epoxy resins, polyurethanes and, of course, piezoelectric materials. The acoustic impedance, measured in Rayls, have to be matched similarly to an electric circuit (2), from a ...
Finite Element Model for Simulating the Inspection of Steel Tubes Using Electromagnetic Acoustic Transducers - new
P. Sun, X. Ding, X. Wu, M. Cong
School of Mechanical Science & Engineering, Huazhong University of Science and Technology, Wuhan, China
Steel tubes are widely used in industries. In order to ensure the safety and reliability of industrial processes, electromagnetic acoustic transducers (EMATs) based guided wave technology has been developed for inspecting stainless steel tubes regularly. Theoretical models and finite element modes have been built to investigate the EMAT technology. However, existing models mainly focused on ...
N. Nama , R. Barnkob , C. J. Kähler , T. J. Huang , F. Costanzo 
 Department of Engineering Science and Mechanics, Pennsylvania State University, PA, USA
 Institute of Fluid Mechanics and Aerodynamics, Bundeswehr University Munich, Neubiberg, Germany
Introduction - The ability to precisely manipulate fluid and particles at microscales is one of the essential requirements for various lab-on-a-chip applications such as drug diagnostics, chemical synthesis etc. Recently, the nonlinear interaction of surface acoustic waves (SAW) with fluid at microscales has been utilized to achieve this aim. When surface acoustic waves interact with fluid ...
Infrasound Assessment of the Roller Compacted Concrete Dam: Case Study of the Portugues Dam in Ponce, PR
H. Diaz-Alvarez , V. P. Chiarito , S. McComas , M. H. McKenna ,
 U.S. Army Engineer Research and Development Center, Vicksburg, MS, USA
The U.S. Army Corps of Engineers is currently investigating the use of infrasound sensors to monitor the health of structures of interest. Infrasound is low-frequency (2-20 Hz) acoustic energy and is capable of propagating many kilometers from the source structure. Large infrastructure, such as dams, bridges, and buildings emit such signals at their natural or driven frequencies of vibration, ...
L. Fromme , J. Waßmuth , D. Wehmeier ,
 Bielefeld University of Applied Sciences, Bielefeld, Germany
The knowledge of the acoustical transfer paths in active noise control systems is very important for the performance of the system. Unfortunately, simulation is challenging since even simple configurations require comprehensive experience in physics and modeling. Two test setups were chosen for basic investigations on modeling, simulation and validation. The first results presented here are ...
N. Krishnan, H. Nemade[1,2], and R. Paily
Centre for Nanotechnology, Indian Institute of Technology Guwahati, Assam, India
Department of Electronics and Communication Engineering, Indian Institute of Technology, Assam, India
In this paper, we discuss a simplified finite element method simulation of surface acoustic wave (SAW) delay line hydrogen sensor using COMSOL Multiphysics. A delay line SAW sensor consists of a transmitting interdigital transducer (IDT) and a receiving IDT separated by a few wavelengths. In this work, the number of degrees of freedom to solve for the SAW delay line sensor model ...