Investigation On Aerodynamic Characteristics Of Mini Trailing Edge Device Applied In Helicopter Rotor

To improve helicopter aerodynamic and flight performance,the paper take the rotor which installed with the mini trailing edge lift enhancement device as research object.The article do research on the aerodynamic characteristics of Mini Trailing edge device.First,By means of solving two dimensional Navier-Stokes equations,the first chapter calculate the static aerodynamic characteristics of the airfoil and make the study of Mach number and Reynolds numbers effects on the airfoil aerodynamic.Analysis indicated that the mini trailing edge devices can effectively improve the aerodynamic performance at the high induced angle.With the increase of Mach number,the lift line slope increased,the stall angle of attack of airfoil will be down.With the increase of Reynolds number,the lift-to-drag ratio improved.Based on the design of experiments method,the paper established the response surface approximation model,Using parameter sensitivity analysis methods to analyze the structure parameters of mini flap influence on airfoil aerodynamic,found that the vertical height of the flap had the greatest influence on performance of airfoil.Because of the helicopter rotor blade include roll motion,feather motion and lag motion,so do further research on the mini trailing device which can be deployable for analyzing the effect of dynamic aerodynamic performance of airfoil,respectively studying the deployable flap effects on airfoil of the dynamic motion,the modest stall and deep stall performance,found that the flaps can effectively delay the dynamic stall.At last,By using theory of CFD momentum source calculate the lift and power of rotor to analyze the mini trailing lift enhancement device's influence on helicopter hovering flight performance,the results implied that at the same pitch angle,adding mini flap could improve the lift of the rotor,Under the high pitch Angle,the mini flap can effectively reduce rotor required power.When helicopter forward flight with the mini –trailing edge device which deployable at the suitable form can reduce the required power.At the economic speed,the required power will be reduced 2 percent.