Design Concepts for Adaptive Airfoils with Dynamic Transonic Flow Control

Modie cations to design of airfoils for use in unsteady transonic e ows are carried out by means of realistic geometry modeling and systematic removal of recompression shocks in the transonic region. A procedure for designing deformable airfoils for helicopter rotor blades is introduced. A baseline shock-free airfoil is created by combining systematic and optimization methods. Two analytical models of deformation are considered. Their ability to control dynamic stall is investigated numerically by using a two-dimensional, time-accurate, implicit Navier‐Stokes code. Results indicate the great potential for the controlled deformation of airfoils for helicopter applications. Dynamic stalling of airfoils at high angles of attack and the appearance of strong recompression shocks at low angles of attack and high Mach numbers are reduced signie cantly. In this way, the results presented will help in extending the design knowledge base for airfoils for helicopter rotors with advanced dynamic stall control.