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The acoustic far-field of rigid bodies in arbitrary motion

โœ Scribed by F. Farassat

Publisher
Elsevier Science
Year
1974
Tongue
English
Weight
961 KB
Volume
32
Category
Article
ISSN
0022-460X

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โœฆ Synopsis

The far-field sound produced by a rigid body in arbitrary motion, with shock discontinuities close to the body, is studied. The analysis is based on the work of Ffowcs Williams and Hawkings [1]. An expression for the far-field sound pressure is obtained in the form of surface and line integrals carried out over a contracting sphere and its intersection with the body and shock surfaces. It is also found that in addition to the quadrupole distribution, the discontinuities in Lighthill stress at the shock, the fluid stresses at the body surface, and the curvatures (principal and mean) of the body and shock surfaces contribute to the sound field. Two examples are worked out.

๐Ÿ“œ SIMILAR VOLUMES

Sources and observers in motion, II: Aco
Sources and observers in motion, II: Acoustic radiation from a small rigid body in arbitrary motion
โœ S.E. Wright; D.J. Lee ๐Ÿ“‚ Article ๐Ÿ“… 1986 ๐Ÿ› Elsevier Science ๐ŸŒ English โš– 388 KB

The theory in reference [1], for a source in rectilinear motion, using time variant analysis and an invariant surface flux source description, is extended here to include arbitrary source motion. The special case of a small rigid object is considered, with motion in a circle used as a simple example

Notes on the acoustic field of rigid bod
Notes on the acoustic field of rigid bodies
โœ F. Farassat ๐Ÿ“‚ Article ๐Ÿ“… 1975 ๐Ÿ› Elsevier Science ๐ŸŒ English โš– 156 KB

## LETTERS TO THE EDITOR NOTES ON THE ACOUSTIC FIELD OF RIGID BODIES This letter concerns the removal of a restriction in the analysis by the writer of the acoustic field ofrigid bodies [1]. It is shown that this restriction is mathematical and could be removed easily by replacing the moving body