Re-expansion method for generalized radiation impedance of a circular aperture in an infinite flange.

The paper applies the re-expansion method to analyze the sound radiation from a flanged circular pipe. The axial velocity in the aperture is expressed by means of some orthogonal polynomials combining the properties of Jacobi's polynomials and hypergeometric functions, and also accounting for the velocity singularities at the edge points of the aperture. This makes it possible to reveal the physical parameters of the problem with a very limited number of terms.

The analysis of plane discontinuities in offset cylindrical waveguides.

This paper applies the re-expansion method for analyzing the effects on the sound field due to planar discontinuities at the junction of two offset circular acoustic waveguides. The normal modes in the two waveguides are expanded at the junction plane into a system of functions accounting for velocity singularities at the corner points. As the new expansion has a high convergence order, only a few terms have to be considered for obtaining the solution of most practical problems.

A microacoustic analysis including viscosity and thermal conductivity to model the effect of the protective cap on the acoustic response of a MEMS microphone.

An analysis is presented of the effect of the protective cover on the acoustic response of a miniature silicon microphone. The microphone diaphragm is contained within a small rectangular enclosure and the sound enters through a small hole in the enclosure's top surface. A numerical model is presented to predict the variation in the sound field with position within the enclosure.

Viscous damping and spring force calculation of regularly perforated MEMS microstructures in the Stokes' approximation.

There are a number of applications for microstructure devices consisting of a regular pattern of perforations, and many of these utilize fluid damping. For the analysis of viscous damping and for calculating the spring force in some cases, it is possible to take advantage of the regular hole pattern by assuming periodicity. Here a model is developed to determine these quantities based on the solution of the Stokes' equations for the air flow.

A porous elastic model for bacterial biofilms: application to the simulation of deformation of bacterial biofilms under microfluidic jet impingement.

The presence of bacterial biofilms is detrimental in a wide range of healthcare situations especially wound healing. Physical debridement of biofilms is a method widely used to remove them. This study evaluates the use of microfluidic jet impingement to debride biofilms.