Study on the influence of flow on parametric acoustic array modal response in surface fluctuation waveguides

This paper analyzes the parametric sound field in a waveguide and studies the influences of the flow velocity and surface fluctuation on the order of parametric difference frequency sound selective excitation. The Green's function solution for the difference-frequency wave describing the propagation of difference-frequency sound in a low Mach number and surface fluctuation waveguides is given. The difference-frequency sound field in the waveguide by discussing the effect of flow on the virtual source of the parametric array in the pump wave's difference grazing angle. It is shown that the waveguide surface wave will affect the horizontal wavenumber of the difference frequency sound field of the parametric array, causing the difference-frequency sound field's amplitude and phase to fluctuate. Simultaneously, the flow velocity in the waveguide will affect the relationship between the order of modal selective excitation and the pump wave's grazing angle when there is a flow in the waveguide, resulting in the change of the modal order and the intensity of the modal excitation of the difference-frequency sound field. It has an excellent guide on the long-distance propagation of the parametric difference-frequency sound field in the waveguide. (C) 2022 Published by Elsevier B.V.

Automated summary

This paper analyzes the parametric sound field in a waveguide and studies the influences of the flow velocity and surface fluctuation on the order of parametric difference frequency sound selective excitation. The results show that the flow velocity and surface fluctuation in the waveguide affect the amplitude, phase, and modal excitation of the difference-frequency sound field.