High-Performance Airfoil with Moving Surface Boundary-Layer Control

All airfoils are known to stall at high angles of attack as a result of flow separation, resulting in a sudden loss of the lift force. To avoid flow separation, it is necessary to introduce some form of boundary-layer control. The present study focuses on the performance of an airfoil with moving surface boundary-layer control (MSBC). Effects of the angles of attack, rate of momentum injection, as well as rotating cylinder surface condition on the surface pressure distribution and aerodynamic coefficients are assessed. A comprehensive study involving wind-tunnel investigation, numerical simulation, and flow visualization clearly demonstrates that the momentum injection through MSBC results in a significant delay in the stall angle (from 10 to 50 deg) and an increase in the lift coefficient by more than 200% at high angles of attack (α 30 deg). A multielement panel method, modeling the flow separation using free vortex lines, predicts the overall aerodynamics of an airfoil with the MSBC quite accurately. The airfoil performance can be improved further by judicious selection of the rotating cylinder surface condition

[1]  V. Modi,et al.  MOVING SURFACE BOUNDARY-LAYER CONTROL AS APPLIED TO TWO-DIMENSIONAL AIRFOILS , 1989 .

[2]  I. Wygnanski,et al.  The control of separation by periodic oscillations , 1994 .

[3]  V. Modi,et al.  Drag reduction of bluff bodies through momentum injection , 1992 .

[4]  G. Erickson,et al.  High Angle-of-Attack Aerodynamics , 1995 .

[5]  Paul K. Chang,et al.  Control of Separation of Flow , 1970 .

[6]  Louis Rosenhead,et al.  Laminar boundary layers , 1963 .

[7]  D. R. Cichy,et al.  Flight tests of a rotating cylinder flap on a North American Rockwell YOV-10 aircraft , 1972 .

[8]  H. Schlichting.  Boundary Layer Theory , 1955 .

[9]  M. Ribaut.  A vortex sheet method for calculating separated two-dimensional flows , 1983 .

[10]  V. J. Modi,et al.  AN APPROACH TO DESIGN OF THE NEXT GENERATION OF FUEL EFFICIENT TRUCKS THROUGH AERODYNAMIC DRAG REDUCTION. , 1991 .

[11]  Yuh-Roung Ou,et al.  Mathematical modeling and numerical simulation in external flow control , 1995 .

[12]  L. Sankar,et al.  Separation control using moving surface effects - A numerical simulation , 1989 .

[13]  S. K. Mukherjea,et al.  Separated flow about a wedge , 1990, The Aeronautical Journal (1968).

[14]  Gustav Victor Lachmann,et al.  Boundary layer and flow control: its principles and application , 1961 .

[15]  Jiezhi Wu,et al.  Vortex Lift at a Very High Angle of Attack with Massively Separated Unsteady Flow , 1993 .

[16]  V. J. Modi,et al.  Moving surface boundary-layer control: Studies with bluff bodies and application , 1991 .