Generalized acoustic energy density

Abstract

The properties of acoustic kinetic energy density and total energy density of sound fields in lightly damped enclosures have been explored thoroughly in the literature. Their increased spatial uniformity makes them more favorable measurement quantities for various applications than acoustic potential energy density (or squared pressure), which is most often used. In this paper, a generalized acoustic energy density (GED), will be introduced. It is defined by introducing weighting factors into the formulation of total acoustic energy density. With an additional degree of freedom, the GED can conform to the traditional acoustic energy density quantities, or it can be optimized for different applications. The properties of the GED will be explored in this paper for individual room modes, a diffuse sound field, and a sound field below the Schroeder frequency.

Generalized acoustic energy density based active noise control in single frequency diffuse sound fields

“…17 shows that minimizing the E Gð1=4Þ response instead of the total acoustic energy density response may lead to improved active control of the global sound energy in a lightly damped enclosure.…”

“…It has been shown that GED based active noise control can further improve the results of ED based ANC below the Schroeder frequency because the GED can be spatially more uniform than the ED for enclosed sound fields. 17 In this paper, GED will be optimized to control noise in a diffuse sound field. This paper is organized as follows.…”

“…15,16 Recently a new energy density quantity, referred to as generalized acoustic energy density (GED), has been introduced. 17 An additional degree of freedom is incorporated into the total acoustic energy density, and thus the quantity can be optimized for different applications. However, the complexity of measurement and computation is not increased compared to the total acoustic energy density.…”

Performance Study of Acoustophoretic Microfluidic Silicon-Glass Devices by Characterization of Material- and Geometry-Dependent Frequency Spectra

“…(5) appears in such a way that the Lagrangian L ac has the dimension of an energy density, the same as L mc , and (ii) the role of the kinetic and potential energies in L ac is reversed when compared to L mc since, in acoustics, the potential energy is the p à p term and the kinetic energy is the gradient-product term [34][35][36].…”