Three dimensional axisymmetric sound propagation through a duct with aerosol

The aim of this study is to develop solutions for the propagation of spinning sound waves in air-filled circular ducts containing water droplets (regarded as an aerosol). There exist several theoretical approaches in literature for treatment of basic (mostly 1-D) aerosol problems with certain limitations, but these approaches are mostly suitable for plane waves. A numerical methodology based on the linearized Euler equations in frequency domain has been developed to account for spatial effects both in azimuthal and radial directions. The interactions between the fluid and particle phases are considered through momentum. The paper also presents an analytical solution with which the numerical solutions are compared. Example solutions for plane and spinning modes are presented with emphasis on the effects of aerosol parameters on propagation characteristics as well as geometric cut-off frequencies.