Journal ArticleDOI
The propagation of plane sound waves in narrow and wide circular tubes, and generalization to uniform tubes of arbitrary cross- sectional shape
Reads0
Chats0
TLDR
In this article, the general Kirchhoff theory of sound propagation in a circular tube is shown to take a simpler form in a regime that includes both narrow and wide tubes, where the sound pressure is essentially constant through each cross section, and the excess density and sound pressure (when scaled by the equilibrium density and pressure of air) are comparable in magnitude.Abstract:
The general Kirchhoff theory of sound propagation in a circular tube is shown to take a considerably simpler form in a regime that includes both narrow and wide tubes. For tube radii greater than rw=10−3 cm and sound frequencies f such that rwf3/2<106 cm s−3/2, the Kirchhoff solution reduces to the approximate solution suggested by Zwikker and Kosten. In this regime, viscosity and thermal conductivity effects are treated separately, within complex density and complex compressibility functions. The sound pressure is essentially constant through each cross section, and the excess density and sound pressure (when scaled by the equilibrium density and pressure of air, respectively) are comparable in magnitude. These last two observations are assumed to apply to uniform tubes having arbitrary cross‐sectional shape, and a generalized theory of sound propagation in narrow and wide tubes is derived. The two‐dimensional wave equation that results can be used to describe the variation of either particle velocity or...read more
Citations
More filters
Proceedings Article
Thermoacoustic engines
W. P. Arnott,R. Raspet,H.E. Bass +2 more
TL;DR: In this paper, an approximate analysis of energy flow and acoustical measurements of a thermoacoustic prime mover with arbitrary cross-sectional geometry is given. But this analysis is restricted to the case of TAEs with circular or parallel slit pore geometry.
Journal ArticleDOI
Dynamic tortuosity and bulk modulus in air‐saturated porous media
Yvan Champoux,Jean‐F. Allard +1 more
TL;DR: In this article, the concept of characteristic length introduced in the definition of the dynamic tortuosity by Johnson, Koplik, and Dashen is extended to express the frequency dependence of the bulk modulus of the saturating fluid at high frequencies.
Journal ArticleDOI
Dynamic compressibility of air in porous structures at audible frequencies
TL;DR: In this paper, a simple model is constructed for the dynamic thermal permeability k′(ω), which is completely analogous to the Johnson et al. [J. 176, 379 (1987)] model of dynamic viscous permeability K(ω).
Journal ArticleDOI
Ultrathin low-frequency sound absorbing panels based on coplanar spiral tubes or coplanar Helmholtz resonators
TL;DR: In this article, the authors report ultrathin sound absorbing panels that completely absorb sound energy with a thickness around one percent of wavelength, and validate the properties of these panels through good agreement between theoretical analysis and experimental measurements.
Journal ArticleDOI
Ultra-thin metamaterial for perfect and quasi-omnidirectional sound absorption
TL;DR: Using the concepts of slow sound and critical coupling, an ultra-thin acoustic metamaterial panel for perfect and quasi-omnidirectional absorption is theoretically and experimentally conceived in this paper.
References
More filters
Journal ArticleDOI
Theory of Propagation of Elastic Waves in a Fluid‐Saturated Porous Solid. I. Low‐Frequency Range
TL;DR: In this article, a theory for the propagation of stress waves in a porous elastic solid containing compressible viscous fluid is developed for the lower frequency range where the assumption of Poiseuille flow is valid.
Journal ArticleDOI
Theory of Propagation of Elastic Waves in a Fluid-Saturated Porous Solid. II. Higher Frequency Range
TL;DR: In this paper, the theory of propagation of stress waves in a porous elastic solid developed in Part I for the low-frequency range is extended to higher frequencies, and the breakdown of Poiseuille flow beyond the critical frequency is discussed for pores of flat and circular shapes.
Book
Theory of sound
TL;DR: In this article, the Laplace's functions of T, F, V are simultaneously reducible to sums of squares, where T is the length of a string, F is the degree of freedom of the string, and V is the size of the chord.