Experimental and Numerical Investigation of Interaction Between Rotor and Wing at High Advance Ratio

In this paper, an experimental and numerical study of a rotor interacting with wing of three different aspect ratios at an advance ratio of 0.5 is described. Those three wings have the equal area and fixed at an angle of attack of 8 degrees. One wing is installed at 3 different vertical positions and three different horizontal locations to investigate the influence of the wing position on the interaction. The calibration and correction process of the measurement is described, and the results are compared to pre-test CFD simulations. Numerical simulations based on simplified rotor and wing-body models have been carried out ahead of the wind-tunnel testing. Due to the existence of rotor-test-stand and the rotorhub which are not included in the CFD simulations, the measured aerodynamic performance deviated from the CFD results remarkably. By applying angle-of-attack and drag offset corrections which remove the influence of the rotortest-stand, the wing performance is found in good agreement with the CFD results. Also, applying hub-correction which is based on measured hub-only aerodynamic force components, and the angle-of-attack correction, the corrected isolated rotor performance in high advance ratio agrees satisfactorily with the CFD data. It is found that due to the rotor/wing interaction, the overall lift-to-effective drag ratios decrease about 12% at the advance ratio of 0.5.