Development of the pneumatic twisteron through the use of circulation control technology.

摘要

This work combines the induced drag reduction concept of conventional twisterons with the lift augmentation of circulation control technology. Conventional twisterons utilize spanwise variations in flap deflection to minimize the induced drag generated by a conventional wing. It was found that, for a circulation-controlled wing, similar drag reductions could be achieved through the use of pneumatic twist (i.e., spanwise variations in blowing strength).; Drag-reducing pneumatic twists at lift coefficients of 0.5 and 1.0 were found for a rectangular circulation-controlled wing with an aspect ratio of 20 and 15-percent-thick elliptic airfoils through the use of computational fluid dynamics modeling. It was found that pneumatic twist can reduce induced drag by up to 26 percent and total drag by up to 30 percent. For applications where circulation-controlled wings are of use, the pneumatic twisteron shows great promise for allowing those wings to perform more efficiently.