M. K. Nguyen, R. Haettel, A. Daneryd
KTH, Stockholm, Sweden
ABB Corporate Research,Västerås, Sweden
Induction motors, as any other industrial products, have to comply with various requirements on noise levels. Therefore, it is essential to use an appropriate prediction tool to verify and optimize the design of an induction motor with respect to the acoustic performances. The paper will focus on the prediction of the magnetic noise generated and radiated by a specific motor. The challenge is ...
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 ...
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 ...
D. Groulx, A. Bharath, S. Campbell
Department of Mechanical Engineering, Dalhousie University, Halifax, NS, Canada
The field of underwater acoustics research is constantly growing with the ongoing improvement of acoustic measuring techniques. An acoustic hydrophone receiver is a passive listening device which is widely used in biological research and sonar technology. The hydrophone however suffers from turbulence generated noise created by its presence in ever faster flow. This work aims to analyze the ...
R. Haettel, A. Daneryd, M. Kavasoglu, C. Ploetner
ABB Corporate Research, Västerås, Sweden
ABB Transformers, Varennes, QC, Canada
Today, low noise is a mandatory feature for power transformers to comply with customer specifications and environmental regulations. Therefore, it is crucial to develop sound prediction tools with sufficient accuracy to avoid overkill margins in design and costly modifications after transformer completion. The paper will focus on core noise which is a typical multiphysics phenomenon involving ...
C. Thiagarajan, G. Shenoy, B. S. Shenoy
ATOA Scientific Technologies Pvt Ltd, Whitefield, Bangalore, India.
Department of Mechanical & Manufacturing Engineering, Manipal Institute of technology, Manipal, India
Department of Aeronautical & Automobile Engineering, Manipal Institute of Technology, Manipal, India
Vibration and Dynamic performances of the rotating machinery are conventionally evaluated based on the dominant structural forces such as the centrifugal forces. The increase in rotational speed, miniaturization and performance, demands for improved and accurate evaluation of the vibration performance. The inclusion of coupled effects of fluid and centrifugal forces can contribute significantly ...
L. Spicci, and M. Cati
Esaote SpA, Florence, Italy
The technology involved in high performance ultrasound imaging probes needs a reliable model to help in new projects development and performance simulations. To achieve a useful model, it is necessary to use correct values for all material parameters involved in the electro-acoustical performances of the piezoelectric material, but unfortunately some of these parameters are known only with high ...
Simulation of a New PZT Energy Harvester with a Lower Resonance Frequency Using COMSOL Multiphysics® - new
H. Elbahr, T. Ali[1,2], A. Badawi, S. Sedky
Zewail City of Science and Technology - Cairo, Cairo, Egypt
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 ...
Zhejiang Electro-Acoustic R&D Center, CAS, Zhejiang, China
扬声器的失真问题一直受电声业界的关注，尤其是谐波失真，它是影响扬声器重放声音音质的主要因素之一。 本文提出了一种基于 COMSOL Multiphysics® ...
R. Sugumar, C. S. Kumar, T. K. Datta
Sharda University, Greater Noida, Uttar Pradesh, India
MVN University, Palwal, Haryana, India
Indian Institute of Technology Delhi, New Delhi, Delhi, India
Earthquakes have always been a threat to the safety of buildings, sometimes even causing fatality due collapse of the structure. Various methods have evolved in the recent past to control/reduce the response of a structure subjected to earthquake forces. One of the widely used passive control methods is Base Isolation System. This paper discusses the study of the response of the base isolated ...