Nonsinusoidal path optimization of a flapping airfoil

Date

2007-08-01

Author

Kaya, Mustafa
Tuncer, İsmail Hakkı

Metadata

Show full item record

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

Item Usage Stats

235
views

0
downloads

The path of a flapping airfoil undergoing a combined, nonsinusoidal pitching and plunging motion is optimized for maximum thrust and/or propulsive efficiency. The nonsinusoidal, periodic flapping motion is described using nonuniform rational B splines. A gradient based algorithm is then employed for the optimization of the nonuniform rational B-spline parameters. Unsteady, low speed laminar flows are computed using a Navier-Stokes solver in a parallel computing environment. The numerical evaluation of the gradient vector components, which requires unsteady flow solutions, is also performed in parallel. It is shown that the thrust generation may significantly be increased in comparison to the sinusoidal flapping motion. For a maximum thrust generation, the airfoil stays at about a constant angle of attack during the upstroke and the downstroke, and may reach very high effective angle of attack values. The pitching motion mostly occurs at the minimum and maximum plunge positions.

Subject Keywords

Aerospace Engineering

URI

https://hdl.handle.net/11511/41650

Journal

AIAA JOURNAL

DOI

https://doi.org/10.2514/1.29478

Collections

Department of Aerospace Engineering, Article

Suggestions

OpenMETU
Core

Optimization of Flapping Motion Parameters for Two Airfoils in a Biplane Configuration Kaya, Mustafa; Tuncer, İsmail Hakkı; Jones, Kevin D.; Platzer, Max F. (American Institute of Aeronautics and Astronautics (AIAA), 2009-03-01) Flapping motion parameters of airfoils in a biplane configuration are optimized for maximum thrust and/or propulsive efficiency. Unsteady, viscous flowfields over airfoils flapping in a combined plunge and pitch are computed with a parallel flow solver on moving and deforming overset grids. The amplitudes of the sinusoidal pitch and plunge motions and the phase shift between them are optimized for a range of flapping frequencies. A gradient-based optimization algorithm is implemented in a parallel computing...
Mathematical model development of the anti torque system of a notar helicopter Bakır, Hüseyin Murat; Yavrucuk, İlkay; Department of Aerospace Engineering (2008) The anti-torque mechanism of a NOTAR helicopter is a complex system including vertical tail and pressurized tail boom which provides air ejection used for both circulation control around the boom and creating directed jet air at the end of the boom. This thesis targets the modeling of this mechanism and integrating it to a helicopter simulation model. Flight tests are performed on the MD 600N helicopter to verify the results. Finally, the simulation is compared with flight test data.
Accurate position control of a flapping-wing robot enabling free-flight flow visualisation in a wind tunnel Karasek, Matej; Perçin, Mustafa; Cunis, Torbjorn; van Oudheusden, Bas W.; De Wagter, Christophe; Remes, Bart D. W.; de Croon, Guido C. H. E. (SAGE Publications, 2019-10-02) Flow visualisations are essential to better understand the unsteady aerodynamics of flapping wing flight. The issues inherent to animal experiments, such as poor controllability and unnatural flapping when tethered, can be avoided by using robotic flyers that promise for a more systematic and repeatable methodology. Here, we present a new flapping-wing micro air vehicle (FWMAV)-specific control approach that, by employing an external motion tracking system, achieved autonomous wind tunnel flight with a maxi...
Computational study of flapping airfoil aerodynamics Tuncer, İsmail Hakkı (American Institute of Aeronautics and Astronautics (AIAA), 2000-05-01) Unsteady, viscous, low-speed flows over a NACA 0012 airfoil oscillated in plunge and/or pitch at various reduced frequency, amplitude, and phase shift are computed. Vortical wake formations, boundary-layer flows at the leading edge, the formation of leading-edge vortices and their downstream convection are presented in terms of unsteady particle traces. Flow separation characteristics and thrust-producing wake profiles are identified. Computed results compare well with water tunnel flow visualization and fo...
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...

Citation Formats

M. Kaya and İ. H. Tuncer, “Nonsinusoidal path optimization of a flapping airfoil,” AIAA JOURNAL, pp. 2075–2082, 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41650.