Numerical Investigation of the Effect of Leading Edge Geometry on Dynamic Stall of Airfoils
Grohsmeyer, Steven P.
Ekaterinaris, John A.
Platzer, Max F.
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The dynamic stall of pitching airfoils is investigated by the numerical solution of the full compressible unsteady two-dimensional Navier-Stokes equations using an alternating-direction-implicit scheme. The flow is assumed to be fully turbulent, and the turbulent stresses are modelled by the Baldwin-Lomax eddy viscosity model. The objective of this study is to investigate the influence of the leading edge geometry on unsteady flow separation. For this purpose three airfoils are analyzed, namely, the NACA 0012 baseline airfoil, the NACA 0012-63 having the same leading edge radius but different contouring forward of maximum thickness, and the NACA 0012-33 having a smaller leading edge radius. It is found that a larger leading edge radius, thicker contouring of the forward part of the airfoil, or increasing pitch rate results in delaying flow separation and formation of the dynamic stall vortex to a higher angle of attack, yielding a higher peak lift coefficient. Within the scope of this study, incipient flow reversal was found to occur in response to essentially the same critical pressure gradient distribution for different pitch rates and Mach numbers.
The article of record as published may be found at http://dx.doi.org/10.2514/6.1991-1798
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
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Grohsmeyer, Steven P. (Monterey, California: Naval Postgraduate School, 1990-09);The dynamic stall of rapidly pitching and oscillating airfoils is investigated by the numerical solution of the full compressible unsteady two- dimensional Navier-Stokes equations using an alternating-direction-implicit ...
Chandrasekhara, M.S.; Platzer, M.F. (1992-11);The research was carried out in the Compressible Dynamic Stall Facility, CDSF, at the Fluid Mechanics Laboratory (FML) of NASA Ames Research Center. The facility can produce realistic nondimensional pitch rates experienced ...
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