On the wake pattern of symmetric airfoils for different incidence angles at Re=1000

Download

index.pdf

Date

2016-06-01

Author

Kurtuluş, Dilek Funda

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

210
views

242
downloads

In the current study, numerical simulations are performed in order to investigate effects of incidence angle and airfoil thickness on alternating vortex pattern of symmetric airfoils at Re = 1000. This alternating vortex pattern is found to be significantly varying in shape as the incidence angle increases. The results are obtained with 1 degrees increment from 0 degrees to 41 degrees and then with 10 degrees increment from 40 degrees until 180 degrees. The instantaneous and mean vortex patterns are investigated around 2% thick (NACA 0002) and 12% thick (NACA 0012) airfoils. The mean lift, drag, and pitching moment coefficients in addition to Strouhal number are computed and compared with the results available in literature. It is found that the wake behind the airfoil exhibits a continuous vortex shedding pattern below 8 degrees incidence angle for NACA 0002 and below 7 degrees incidence angle for NACA 0012 at Re = 1000. The wake structures are classified into five different modes according to their pattern obtained from instantaneous and mean vorticity fields by also taking into account the amplitude spectrum of the lift coefficient, the instantaneous and mean aerodynamic force coefficients, velocity fields, and the longitudinal and lateral vortex spacings.

Subject Keywords

Aerospace Engineering

URI

https://hdl.handle.net/11511/35242

Journal

INTERNATIONAL JOURNAL OF MICRO AIR VEHICLES

DOI

https://doi.org/10.1177/1756829316653700

Collections

Department of Aerospace Engineering, Article

Suggestions

OpenMETU
Core

Analysis of stability and trasitionin flat plate compressible boundary layers using linear stability theory Atalayer, H. Senem; Özge, Serkan; Department of Aerospace Engineering (2004) In this study, numerical investigations of stability and transition problems were performed for 2D compressible boundary layers over a flat plate in adiabatic wall condition. Emphasis was placed on linear stability theory. The mathematical formulation for 3D boundary layers with oblique waves including detailed theoretical information was followed by use of the numerical techniques for the solution of resulting differential system of the instability problem, consequently an eigenvalue problem. First, two-di...
Near-surface topology and flow structure on a delta wing Yavuz, Mehmet Metin; Rockwell, D (American Institute of Aeronautics and Astronautics (AIAA), 2004-02-01) The streamlines, and the corresponding patterns of velocity and vorticity, are characterized on a plane immediately adjacent to the surface of a delta wing using a laser-based technique of high-image-density particle image velocimetry. This technique provides the sequence of instantaneous states, as well as the corresponding time-averaged state, of the near-surface streamline topology and the associated critical points. These topological features are interpreted in terms of patterns of averaged and unsteady...
Time-domain calculation of sound propagation in lined ducts with sheared flows Özyörük, Yusuf (American Institute of Aeronautics and Astronautics (AIAA), 2000-05-01) A recent application of the time-domain equivalent of the classical acoustic impedance condition, i.e., the particle displacement continuity equation, to numerical simulations of a Bow-impedance tube in the time domain yielded reasonably good results with uniform mean flows. The present paper extends this application to include sheared mean-flow effects on sound propagation over acoustically treated walls. To assess the prediction improvements with sheared flows, especially at relatively high Mach numbers, ...
Nonlinear flutter calculations using finite elements in a direct Eulerian-Lagrangian formulation Seber, Guclu; Bendiksen, Oddvar O. (American Institute of Aeronautics and Astronautics (AIAA), 2008-06-01) A fully nonlinear aeroelastic formulation of the direct Eulerian-Lagrangian computational scheme is presented in which both structural and aerodynamic nonlinearities are treated without approximations. The method is direct in the sense that the calculations are done at the finite element level, both in the fluid and structural domains, and the fluid-structure system is time-marched as a single dynamic system using a multistage Runge-Kutta scheme. The exact nonlinear boundary condition at the fluid-structure...
Effect of Thickness-to-Chord Ratio on Flow Structure of a Low Swept Delta Wing Gulsacan, Burak; Sencan, Gizem; Yavuz, Mehmet Metin (American Institute of Aeronautics and Astronautics (AIAA), 2018-12-01) The effect of thickness-to-chord (t/C) ratio on flow structure of a delta wing with sweep angle of 35 deg is characterized in a low-speed wind tunnel using laser-illuminated smoke visualization, particle image velocimetry, and surface pressure measurements. Four different t/C ratios varying from 4.75 to 19% are tested at angles of attack, 4, 6, 8, and 10 deg, for Reynolds numbers Re =1 x 10(4) and 3.5 x 10(4). The results indicate that the effect of thicknessto-chord ratio on flow structure is quite substan...

Citation Formats

D. F. Kurtuluş, “On the wake pattern of symmetric airfoils for different incidence angles at Re=1000,” INTERNATIONAL JOURNAL OF MICRO AIR VEHICLES, pp. 109–139, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35242.