The dynamic interactions between an incident line vortex and a symmetric Joukowski airfoil on elastic translational support are formulated analytically and evaluated numerically, where the unsteady shedding of vorticity from the airfoil trailing edge is modeled by the emended Brown and Michael equation. This mathematical framework explores the effects of initial vortex placement, vortex strength, and the system aeroelastic parameters on the selection of the vortex trajectory to pass either above or below the airfoil, where special attention is paid to the conditions where direct impingement occurs.
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Acoustic emission of aeroelastic vortex-gust interactions
The coupled interaction between an unsteady vortical flow and dynamics of an aerodynamic structure is a canonical problem for which analytical studies have been typically restricted to either static or prescribed structural motions. The present effort extends beyond these restrictions to include a Joukowski airfoil on elastic supports and its aeroelastic influence on the incident vortex, where it is assumed that all vorticity in the flow field can be represented by a collection of line vortices. An analytical model for the vortex motion and the unsteady fluid forces on the airfoil is derived from inviscid potential flow, and the evolution of the unsteady airfoil wake is governed by the Brown and Michael equation. The aerodynamic sound generated by the aeroelastic interaction of an incident vortex, shed Brown-Michael vortices, and the moving airfoil is estimated for low-Mach-number flows using the Powell-Howe acoustic analogy.
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- NSF-PAR ID:
- 10156779
- Date Published:
- Journal Name:
- International Congress on Acoustics
- ISSN:
- 2226-7808
- Page Range / eLocation ID:
- 604-611
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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