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Simulation of a New PZT Energy Harvester with a Lower Resonance Frequency Using COMSOL Multiphysics® - new

H. Elbahr[1], T. Ali[1,2], A. Badawi[1], S. Sedky[1]
[1]Zewail City of Science and Technology - Cairo, Cairo, Egypt
[2]Cairo University, Cairo, Egypt

Energy harvesting from environmental vibration nowadays is feasible because of natural oscillations like that caused by air or liquid flow and by exhalation or the heartbeat of a human body. This vibration frequency is typically low (in order of less than 1 kHz). Accordingly, low-frequency vibration based energy harvesting systems are an important research topic; these systems can be used for ...

Analyzing Muffler Performance Using the Transfer Matrix Method 

K. Andersen
Dinex Emission Technology A/S, Middelfart, Denmark

Exhaust noise must meet legislation targets, customer expectations and cost reduction which call for design optimization of the exhaust systems in the design phase. One solution is to use 3 dimensional linear pressure acoustics and calculate the transfer matrix of the muffler. The transfer matrix is the basis for calculating either the insertion loss or transmission loss of a muffler. The 3D ...

Simulation of Impact Damage in a Composite Plate and Its Detection

V. Pavelko[1], I. Pavelko[1], M. Smolyaninovs[1], H. Pffeifer[2], M. Wevers[2]
[1]Riga Technical University, Riga, Latvia
[2]Catholic University Leuven, Leuven, Belgium

A problem of damage prediction in aircraft structure and its non-destructive evaluation is very important for aircraft structural health assessment. The analysis of the features of direct impact of thin-walled laminate component of aircraft was performed by COMSOL Multiphysics software. Mainly the GFRC and CFRC laminates were selected in form either thin separate plate or sandwich structure. The ...

An Improved Loudspeaker Frequency Response by Using a Structure of Rigid Absorptive Panel in a Vented Cabinet - new

R. Balistreri[1]
[1]Community Light & Sound Inc., Chester, PA, USA

When placing a loudspeaker in a cabinet, standing waves inside the cabinet affect the frequency response with ripples. This peaks and dips due to pressure cancellation inside the cabinet have an effect on the diaphragm and generating sound out from the vents. If it was in a condition of total absorption of the sound waves at the back of the diaphragm, the transducer would otherwise have a much ...

Simulation of Acoustic Energy Harvesting Using Piezoelectric Plates in a Quarter-Wavelength Straight-Tube Resonator

B. Li[1], J.H. You[1]
[1]Southern Methodist University, Dallas, TX, USA

An acoustic energy harvesting mechanism at low frequency (~200 Hz) using lead zirconate titanate (PZT) piezoelectric cantilever plates placed inside a quarter-wavelength straight-tube resonator has been studied using COMSOL Multiphysics 4.3 and compared with experimental data. When the tube resonator is excited by an incident wave at its acoustic eigenfrequency, an amplified acoustic resonant ...

Laser-Ultrasonics Wave Generation and Propagation FE Model in Metallic Materials

A. Cavuto[1], G.M. Revel [1], M. Martarelli [2], F. Sopranzetti [2]
[1]Università Politecnica delle Marche, Ancona, Italy
[2]Università e-Campus, Novedrate (CO), Italy

A 2D axisymmetric model was considered in order to evaluate the propagation paths of the ultrasonic waves generated inside an aluminum plate sample due to a rapid thermal expansion produced by laser pulse. Laser Doppler Vibrometer is used to experimentally validate the numerical results of the wave propagation in the material. The presented numerical model is able to identify directivity ...

Scale-up Design of Ultrasound Irradiator for Advanced Oxidation Process (AOP) Using COMSOL Multiphysics® Simulation

Z. Wei[1]
[1]The Ohio State University, Columbus, OH, USA

Ultrasound is a promising green technology for the advanced oxidation process (AOP) since it adds no chemicals to the treated water. In this paper, COMSOL Multiphysics® was used as a tool to design and characterize an ultrasound irradiator with multi-stepped configuration, which aims to overcome disadvantages of typical irradiators and to enhance contaminant removal in large-scale water ...

Modal Analysis of Functionally-Graded Metal-Ceramic Composite Plates - new

E. Gutierrez-Miravete[1], W. L. Saunders II[2], K. Pendley[3]
[1]Rensselaer at Hartford, Hartford, CT, USA
[2]General Dynamics Electric Boat, Groton, CT, USA
[3]United Technologies - Pratt & Whitney, East Hartford, CT, USA

The determination of the modes of vibration of Functionally Graded-Metal-Ceramic Composite plates is important in practice in order to prevent undesired resonances in structural components. This paper describes the application of COMSOL Multiphysics® software for the determination of the modes of vibration of Aluminum A356-T6Alloy-ZrO2 FG-MCC square plates.

Effect of Length and Porosity on the Acoustic Performance of Concentric Tube Resonators

D. Neihguk [1], A. Prasad [1],
[1] Mahindra & Mahindra Ltd., Chennai, India

The acoustic performance of an acoustically short Concentric Tube Resonator (CTR) is investigated to find an optimum porosity for a given length to diameter ratio. The study is motivated by the following practical difficulties encountered in automotive exhaust noise control: 1. Increasing trend of downsized engine and increase in power to weight ratio of engine for better fuel economy. 2. The ...

Simulation of a Piezoelectric Loudspeaker for Hearing Aids and Experimental Validation - new

G. C. Martins[1], P. R. Nunes[1], J. A. Cordioli[1]
[1]Federal University of Santa Catarina, Florianópolis, SC, Brazil

The use of piezoelectric materials in hearing aid loudspeakers, also called receivers, presents technical and economic advantages such as reducing the number of parts of the system and its manufacturing cost. However, the performance of such systems is still not competitive when compared to traditional electrodynamic loudspeakers. In order to achieve an appropriate performance, one option is to ...