Control effects of typical motion parameters of Trailing-Edge Flap (TEF) on the dynamic stall characteristics of the rotor are investigated. To overcome the shortcoming of the deformable grid approach, which may result in distortion of grid, a moving-embedded grid method is developed to predict the flowfield of the rotor with TEF control in the forward flight. Based on Unsteady Reynolds Averaged Navier-Stokes (URANS) equations, k-ω Shear Stress Transport (SST)turbulence model, Roe-MUSCL scheme, implicit LU-SGS scheme, parallel techniques and dual-time method, a high-efficiency CFD method is developed to predict the unsteady aerodynamic characteristics of rotor with TEF control. A comparison of calculation and experiment results of the normal force of the forward flight of the SMART rotor with TEF demonstrates validity of the proposed CFD method. Control effects of the forward flight of the rotor via trailing-edge flap are analyzed. Effects of the parameters including the angular amplitude, non-dimensional frequency, location and width of the trailing-edge flap on the aerodynamic characteristics of the rotor are explored with the same maneuvering. Parametric analyses of rotor aerodynamic characteristics are further investigated in the trimming condition. The results indicate that with TEF, rotors can reach their full lift potential in the advancing side, and the drag and torque of the rotor caused by dynamic stall in retreating blades can be reduced. With the same rotor thrust, the drag and torque coefficients of the rotor can be reduced by about 17% and 29% respectively control and the lift-to-drag ratio is increased by 14% via TEF.
MA Yiyang
,
ZHAO Qijun
. Control mechanism and parameter analyses of aerodynamic characteristics of rotor via trailing-edge flap[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2018
, 39(5)
: 121671
-121671
.
DOI: 10.7527/S1000-6893.2018.21671
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