An indicator design method of advancing blade concept rotor airfoil based on X2TD aircraft

In order to simulate the aerodynamic characteristics of high speed helicopter blade sections, an operating condition analysis method for helicopter rotor airfoil is developed and verified based on the CFD and CAMRAD Ⅱ method. And an airfoil indicator design method, named “α-Ma plane lift-drag ration contour”, is constructed, taking into account of the characteristics of Mach number and angle of attack of a rotating blade. The method is suitable for the airfoil indicator design in full azimuth and full span blade sections, and is used to analyze the Advancing Blade Concept rotor airfoils. Based on the study of ABC rotor flow field characteristics of large reverse flow field, strong radial flow, strong compressible flow, lift offset and variable rotation speed as well as the further analysis of the aerodynamic characteristics of advancing and retreating side blade airfoil section for both upper and lower rotors, the improvement of airfoil selection criteria and design indicator have been done. The computational results are in good agreements with the reference results. The airfoil indicator design method and computational results are useful for the intensively studying of ABC rotor aerodynamic design.