Effect of reduced frequency on dynamic stall of a pitching airfoil in a turbulent wake

Anurag Gandhi, Brandon Merrill, Yulia Peet

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

In this paper, we investigate the influence of an airfoil pitching frequency (reduced frequency) on dynamic stall behavior of a NACA0012 airfoil oscillating in a turbulent wake with Direct Numerical Simulations. The presence of an upstream turbulence with dynamically oscillated blades and airfoils is associated with the ambient flow unsteadiness and is encountered in many operating conditions. We have recently developed a methodology that allows us to study the effects of wake turbulence on an oscillating airfoil with high-fidelity moving overlapping grid approach in high-order numerical formulation. The turbulent wake is generated by a small solid cylinder placed upstream of an oscillating airfoil, and the vortices shed from the upstream cylinder interfere with the pitching airfoil dynamics that alters the dynamic stall characteristics. In this paper, we study how the effects of the wake turbulence on the dynamic stall change when the reduced frequency is changed. We compare two reduced frequencies for the airfoil oscillation, k = 0:16 and 0:25, and document the corresponding flow-fields and aerodynamic coefficients. We focus on understanding how the vortex dynamics change in different cases and how it effects the airfoil aerodynamic characteristics.

Original languageEnglish (US)
Title of host publicationAIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting
PublisherAmerican Institute of Aeronautics and Astronautics Inc.
ISBN (Electronic)9781624104473
DOIs
StatePublished - 2017
Event55th AIAA Aerospace Sciences Meeting - Grapevine, United States
Duration: Jan 9 2017Jan 13 2017

Other

Other55th AIAA Aerospace Sciences Meeting
CountryUnited States
CityGrapevine
Period1/9/171/13/17

Fingerprint

Airfoils
Turbulence
Aerodynamics
Vortex flow
Direct numerical simulation
Flow fields

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Gandhi, A., Merrill, B., & Peet, Y. (2017). Effect of reduced frequency on dynamic stall of a pitching airfoil in a turbulent wake. In AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting [AIAA 2017-0720] American Institute of Aeronautics and Astronautics Inc.. https://doi.org/10.2514/6.2017-0720

Effect of reduced frequency on dynamic stall of a pitching airfoil in a turbulent wake. / Gandhi, Anurag; Merrill, Brandon; Peet, Yulia.

AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting. American Institute of Aeronautics and Astronautics Inc., 2017. AIAA 2017-0720.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Gandhi, A, Merrill, B & Peet, Y 2017, Effect of reduced frequency on dynamic stall of a pitching airfoil in a turbulent wake. in AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting., AIAA 2017-0720, American Institute of Aeronautics and Astronautics Inc., 55th AIAA Aerospace Sciences Meeting, Grapevine, United States, 1/9/17. https://doi.org/10.2514/6.2017-0720
Gandhi A, Merrill B, Peet Y. Effect of reduced frequency on dynamic stall of a pitching airfoil in a turbulent wake. In AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting. American Institute of Aeronautics and Astronautics Inc. 2017. AIAA 2017-0720 https://doi.org/10.2514/6.2017-0720
Gandhi, Anurag ; Merrill, Brandon ; Peet, Yulia. / Effect of reduced frequency on dynamic stall of a pitching airfoil in a turbulent wake. AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting. American Institute of Aeronautics and Astronautics Inc., 2017.
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