Vortex flow aerodynamics behind a symmetric airfoil at low angles of attack and Reynolds numbers

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2021-11-01

Author

Kurtuluş, Dilek Funda

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The low Reynolds number aerodynamics is important to investigate for micro air vehicle applications. The current paper covers numerical simulations to present the downstream development of the wake patterns and detailed analysis of the vortices generated at the downstream of NACA 0012 airfoil around the critical angle of attack where the instantaneous vortex patterns are oscillatory and differ from the mean vortex pattern for low Reynolds numbers ranging from 1000 to 4000. The instantaneous and mean aerodynamic forces, pressure and skin friction coefficients, and vorticity values are compared in addition to the path of the vortex centers, their longitudinal and lateral spacings, Karman spacing ratios, and distortion ratios at the wake of the airfoil in regard to the different Reynolds numbers investigated. The streamwise and crosswise velocities of the vortex cores and relative velocities at different transverse locations are also discussed and presented in detail. The correlations between different non-dimensional numbers (St, Re, Ro) are obtained at these low Reynolds numbers investigated.

Subject Keywords

Unsteady aerodynamics, low Reynolds number, airfoil wake, Karman spacing ratio, NACA 0012 AIRFOIL, STABILITY

URI

https://hdl.handle.net/11511/94942

Journal

INTERNATIONAL JOURNAL OF MICRO AIR VEHICLES

DOI

https://doi.org/10.1177/17568293211055653

Collections

Department of Aerospace Engineering, Article

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Citation Formats

D. F. Kurtuluş, “Vortex flow aerodynamics behind a symmetric airfoil at low angles of attack and Reynolds numbers,” INTERNATIONAL JOURNAL OF MICRO AIR VEHICLES, vol. 13, pp. 0–0, 2021, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/94942.