Lift Enhancement of a Wing/Strake Using Pneumatic Blowing.

摘要

A low-speed wind-tunnel study to quantitatively measure the lift and drag effects of pneumatically controlling strake and leading-edge vortices generated by a half-span, generic-fighter model was conducted. The study measured the increase in lift and drag on the model throughout a range of angles of attack. The study utilized various blowing tubes of different geometries and orientations. Results showed that blowing produced changes in lift with minimal effect on drag. Blowing appeared to reattach flow during the initial stages of stall. Blowing increased lift a maximum of 9 percent at an angle of attack of 20 degrees, and up to 7 percent at angles of attack greater than 20 degrees. Blowing rates were varied from C sub mu of 0.0094 to C sub mu of 0.022. Near axial blowing produced the largest increases in lift. It was found that lift increases were directly proportional to changes in blowing rate.