This paper proposes a modified boundary condition to improve the room-acoustic prediction accuracy of a diffusion equation model. Previous boundary conditions for the diffusion equation model have certain limitations which restrict its application to a certain number of room types. The boundary condition employing the Sabine absorption coefficient [V. Valeau et al., J. Acoust. Soc. Am. 119, 150...

This paper concerns with the design of an acoustic cavity (transmission suite) for the vibro-acoustic characterization of lightweight panels. This setup has the big advantage of being a small (1150x984x820 mm) which allows the identification of the studied behaviour for both structureand airborne excitation, on panels of different size (from A4 to A2) and thickness (up to 5cm). Particular effor...

The exponentially decaying acoustic pressure of scattered surface acoustic waves (SAWs) at the contact line of a liquid film pinned to filter paper is shown to sustain a high curvature conic tip with micron-sized modulations whose dimension grows exponentially from the tip. The large negative capillary pressure in the film, necessary for offsetting the large positive acoustic pressure at the co...

Ultrasonic pre-treatment of small and pressure saturated Douglas-fir heartwood specimens at 20 kHz fixed frequency with an acoustic horn resulted in increased specific permeability coefficient in both radial and tangential directions. Statistical analysis revealed that there was a high correlation between ultrasonic treatment time and specific permeability coefficient. Improvement rate of perme...

Introduction: Micro perforated panel (MPP) absorbents promise the next generation of sound absorbers as they have significant advantages over other porous adsorbents. In this study, we will investigate the acoustic performance of MPP absorbents made of biodegradable polylactic acid composite reinforced with natural corkwood fibers (PLA/Corkwood) by 3D printing technology. Material and Methods:...

To obtain accurate soil parameters and improve the accuracy of acoustic-soil discrete element simulation model, we studied model’s parameter calibration. The test was carried out using measured acoustic velocity dominant frequency as response value (index). Firstly, Plackett—Burman scheme used to sensitivity ranking wave. that significantly affect wave were obtained: Shear modulus, Poisson’s ra...

The primary objective of this work was the utilization pulsed acoustic wave (PAW) method to explore feasibility measuring soil water content (SWC) based on parameter acquisition (SAPA) system. Acoustic parameters (pulse velocity and attenuation coefficient) were collected from paddy (clay), red (loam), lateritic-red (clay loam) under different SWCs. calibration models pulse velocity, coefficien...