TY - JOUR

T1 - Direct formulation of the supersonic acoustic intensity in space domain

A1 - Fernandez Grande,Efren

A1 - Jacobsen,Finn

A1 - Leclre,Quentin

AU - Fernandez Grande,Efren

AU - Jacobsen,Finn

AU - Leclre,Quentin

PB - American Institute of Physics

PY - 2012

Y1 - 2012

N2 - This paper proposes and examines a direct formulation in space domain of the so-called supersonic acoustic intensity. This quantity differs from the usual (active) intensity by excluding the circulating energy in the near-field of the source, providing a map of the acoustic energy that is radiated into the far field. To date, its calculation has been formulated in the wave number domain, filtering out the evanescent waves outside the radiation circle and reconstructing the acoustic field with only the propagating waves. In this study, the supersonic intensity is calculated directly in space domain by means of a two-dimensional convolution between the acoustic field and a spatial filter mask that corresponds to the space domain representation of the radiation circle. Therefore, the acoustic field that propagates effectively to the far field is calculated via direct filtering in space domain. This paper presents the theory, as well as a numerical example to illustrate some fundamental principles. An experimental study on planar radiators was conducted to verify the validity of the technique. The experimental results are presented, and serve to illustrate the usefulness of the analysis, its strengths and limitations. © 2012 Acoustical Society of America.

AB - This paper proposes and examines a direct formulation in space domain of the so-called supersonic acoustic intensity. This quantity differs from the usual (active) intensity by excluding the circulating energy in the near-field of the source, providing a map of the acoustic energy that is radiated into the far field. To date, its calculation has been formulated in the wave number domain, filtering out the evanescent waves outside the radiation circle and reconstructing the acoustic field with only the propagating waves. In this study, the supersonic intensity is calculated directly in space domain by means of a two-dimensional convolution between the acoustic field and a spatial filter mask that corresponds to the space domain representation of the radiation circle. Therefore, the acoustic field that propagates effectively to the far field is calculated via direct filtering in space domain. This paper presents the theory, as well as a numerical example to illustrate some fundamental principles. An experimental study on planar radiators was conducted to verify the validity of the technique. The experimental results are presented, and serve to illustrate the usefulness of the analysis, its strengths and limitations. © 2012 Acoustical Society of America.

KW - Numerical analysis

KW - Acoustic convolution

KW - Acoustic intensity

KW - Spatial filters

KW - Acoustic field

KW - Acoustic filters

KW - Acoustic radiators

KW - Acoustic wave propagation

U2 - 10.1121/1.3662052

DO - 10.1121/1.3662052

JO - Journal of the Acoustical Society of America

JF - Journal of the Acoustical Society of America

SN - 00014966

IS - 1

VL - 131

SP - 186

EP - 193

ER -