Revisiting the Problem of Sound Field of Point Multi-pole Sources in a Linear Shear Layer

Aero-acoustics refers to the branch of acoustics that studies sonic waves generated via either turbulent air flows or aerodynamic forces interacting with surfaces. Although the problem of sound waves propagation in a transverse shear flow seems to be fully investigated and solved, considering that, Musafir identified, through a general scheme for representing solutions of Lilley¿s equation, that some results in Scott¿s solution for a point quadrupole source in the bi-dimensional linear shear layer are incorrect. The research presented in this book makes an effort at 1) revisiting the problem of propagation of the sound waves emitted from various point sources through a bi-dimensional linear shear layer in order to verify, by comparing the correct quadrupole solution with the one obtained by Scott, 2) studying to which extent conclusions drawn by Scott¿s based on his results are correct or should be altered. The theory is complemented by Matlab codes and case studies, implementing the exact and approximate solutions for different multipole sources close to a linear shear layer. The cases of source located in the uniform flow region and in the shear layer itself will be considered.