RECENT DEVELOPMENTS IN DYNAMIC STALL.

Abstract

The main features of dynamic stall have been discussed with heavy emphasis placed on the vortex-shedding phenomenon. It is noted that the present state of knowledge has been enhanced by potential flow theory, boundary-layer theory, and, to a limited extent, by Navier-Stokes calculations; but most of what is known today has come from experiments and empirical modeling of the aerodynamic forces and moments. Several empirical methods for estimating the forces and moments on oscillating airfoils are explained on the basis of certain fundamental notions of stall delay.