A new numerical method, named the acoustical wave propagator method, is introduced to describe the dynamic characteristics of one-dimensional structures with discontinuities. The acoustical wave propagator is derived and implemented by combining Chebyshev polynomial expansion and fast Fourier transformation. Numerical accuracy of the acoustical wave propagator method is examined and compared wi...

Active room compensation based on wave field synthesis (WFS) has been recently introduced. So far, the verification of the compensation algorithms is only possible through elaborate acoustical measurements. Therefore, a new simulation method is applied that is based on the functional transformation method (FTM). Compared with other simulation techniques, the FTM provides several advantages that...

Far-field acoustical holography methods reconstruct the sound fields mainly based on the simple point source model because of the loss of abundant information compared with near-field acoustical holography (NAH). It brings problems that the reconstructed sound sources are different from the actual measured sound sources especially because of the evanescent waves which attenuate rapidly in the n...

The behaviour of ultrasonic wave propagation through liquid solution has become an important tool for studying physical and chemical properties of liquid solutions. The density, viscosity and ultrasonic velocity of of cholesteryl oleyl carbonate have been studied. From the experimental data various thermo acoustical parameters such as free volume, internal pressure and Rao’s constant and Wada’s...

This paper presents a reduced-order approach to near-field acoustical holography (NAH) that allows the user to account for sound fields generated by multiple spatially separated sources. In this method, an equivalent wave model (EWM) of a given field is formulated to include combinations of planar, cylindrical, spherical, or other elementary wave functions in contrast to an EWM restricted to a ...

A brief review is presented of the theory of flexural edge waves, first predicted in 1960 by Yu K. Konenkov using Kirchhoff plate theory. It is demonstrated that the flexural edge wave is also predicted by Mindlin’s plate theory, and that the prediction agrees with measured data. It is noted that the edge wave was erroneously presented as a new type of bending wave solution in a recently publis...

The theoretical prediction of the acoustical polarization effects in the heterogeneous composites, made of thick elastic solids with thin nematic films, is presented. The numericalanalytical solution to the problem of the different wave propagation exhibits some new physical effects in the low frequency domain: the appearance of the critical frequency and the existence of the narrow transition ...