R. W. Pryor ,
 Pryor Knowledge Systems, Inc., Bloomfield Hills, MI, USA
Crack detection is and has been an active field of exploration, both theoretical and applied for a number of years. It is the belief of this author that the concepts presented herein explore a new methodology for the modeling and the detection of cracks and families of cracks in crystalline solids, polycrystalline solids and high viscosity amorphous materials (glasses). In the case of the ...
S. R. Fischbach ,
 Jacobs ESSSA Group, NASA Marshall Space Flight Center, Huntsville, AL, USA
 Qualis Corporation, Huntsville, AL, USA
Combustion instability modeling of Solid Rocket Motors (SRM) remains a topic of active research. Many rockets display violent fluctuations in pressure, velocity, and temperature originating from the complex interactions between the combustion process, acoustics, and steady-state gas dynamics. Recent advances in defining the energy transport of disturbances within steady flow-fields have been ...
S. Rouabah, A. Chaabi
Electronics Department, Constantine University, Constantine, Algeria
In this work, we have taken a model which is simulated using COMSOL Multiphysics®. It was used as a tool to design, characterize and to simulate an example which is nanofibers based piezoelectric energy generators. The results are compared with other available sources but using with another materials. After applying a pressure on the top of surface of nanogenerator, the output parameters ...
A. Arevalo , D. Conchouso , D. Castro , I. G. Foulds ,
 Computer, Electrical, & Mathematical Sciences & Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
 The University of British Columbia, School of Engineering, Vancouver, BC, Canada
The growth of the electronics industry demand better components for the electronic systems. Such components need to be improve to keep up with the evolution of the digital era. The loudspeaker design has not been changed for almost a century [1-5]. The acoustic transducer is the last analogue component needed for a true digital audio system. We want to validate the feasibility of using an ...
D. Neihguk , A. Prasad ,
 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 ...
A. Prasad , R. C Thiagarajan ,
 ATOA Scientific Technologies, Bengaluru, India
This paper deals with the numerical experiments for early prediction of muffler performance at the design stage. In this experiment, a Reactive Muffler is developed and validated numerically compared to traditional built and test process.
Y. M. Khedkar, S. B. Joshi, P. M. Pawar, B. P. Ronge
SVERI's College of Engineering, Pandharpur, Maharashtra, India
Brahmdevdada Mane Polytechnic, Solapur, Maharashtra, India
Classical hydraulic dampers are flexible devices that are used to attach a component to a mounting base. Vibration amplitude reduction can be achieved by improving the old technique of suspension by bringing in application of Magnetorheological or Electrorheological fluid in it. Due to the controllable characteristics of the material used in the classical hydraulic damper, the design and ...
A. Cavuto, G.M. Revel , M. Martarelli , F. Sopranzetti 
Università Politecnica delle Marche, Ancona, Italy
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 ...
V. Plessky , V. Yantchev 
 GVR Trade SA, Gorgier, Swizterland
 Individual Consultant, Sofia, Bulgaria
Electroacoustic resonators employing surface acoustic waves (SAW) are commercially widely used in RF filters, low noise frequency sources as well as various sensors. In all of these applications the resonance quality factor appears to be a limiting performance factor. Quite often practical Q factors are not limited by the materials, but by design deficiencies, enabling energy loss outside the ...
An Improved Loudspeaker Frequency Response by Using a Structure of Rigid Absorptive Panel in a Vented Cabinet - new
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 ...