Radiation of acoustic waves from a flat channel, approximate solution
https://doi.org/10.18384/2949-5067-2023-4-19-33
Abstract
Aim: to consider the process of emitting a sound wave (main mode) from a semi-infinite channel without a flange when the air inside and outside the channel is at rest, to develop a procedure for approximating the solution, which allows us to obtain the reflection and transformation coefficients of the main mode wave on the channel slice, as well as a directional pattern and spatial distribution of acoustic pressure outside the channel, and compare it with an accurate analytical solution.
Methodology. The solution of the problem is expressed in terms of the eigenfunctions of the continuous and discrete spectrum problem. The conditions of continuity of the solution on the channel slice are used as closure conditions.
Results. Approximate characteristics of sound emission from a channel without flanges are determined, bypassing the Wiener – Hopf procedure.
Research implications. The proposed procedure simplifies obtaining a solution compared to the Wiener – Hopf method, which, in the case of gas moving in the channel, makes it possible to link the sound generation process with the characteristics of the boundary layer on the channel walls.
About the Author
V. A. Zharov
Central Aerohydrodynamic Institute named after N. E. Zhukovsky
Russian Federation
Russian Federation
Vladimir A. Zharov – Dr. Sci. (Phys.-Math.), Leading Researcher
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