Articles techniques et présentations

The vibration of an electrodynamic loudspeaker driver causes a resulting sound pressure. For simple pistonic vibration, there is a simple relationship between the vibration and the sound pressure. For complex vibration patterns, however, different parts of the vibrating surface ... En savoir plus

Introduction In order to understand the detection mechanism of the PZT based nondestructive testing (NDT) technology for interface debonding of CFSTs, numerical simulation on a multi-physical model composed of surface-mounted PZT patches and CFST structural member is established in ... En savoir plus

The sound propagation and absorption properties in porous media under high sound pressure level conditions have been reported elsewhere. Also several analytical and semi-analytical solutions have been developed; however, these solutions are relatively complicated and the provided results ... En savoir plus

In order to satisfy the requirements of modern range measuring technology, photoelectric theodolites gradually develop towards lightweight and minitype design. As a consequence, the mobile theodolite is becoming a hot spot recently. New requirements are raised for the theodolite base ... En savoir plus

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. En savoir plus

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. ... En savoir plus

Mufflers are devices used to attenuate engine exhaust noise. Muffler design has become more challenging as the customers look out for good exhaust sound quality, especially for motorcycles. Performance of a muffler in an automotive exhaust system is characterized by Transmission Loss ... En savoir plus

Engine is a major source of noise in motorcycle. Acoustic analysis of a single cylinder motorcycle engine under combustion load is presented. Engine surface acceleration obtained from vibration analysis is used as input for acoustic analysis. Process automation is carried out using java ... En savoir plus

Microelectromechanical coupled resonating arrays are being used for detecting biological and chemical analytes through mass sensing. Such arrays of perfectly identical resonators can be considered as periodic, ordered, non-localized systems. The change in the eigen parameters of the ... En savoir plus

The paper presents finite element simulation of a surface acoustic wave (SAW) linear motor. The function of SAW linear motor depends on the principle of friction drive provided by SAW propagating on a piezoelectric substrate. The SAW motor comprises of a slider driven by Rayleigh wave ... En savoir plus