Experimental investigation of the effects of different helicopter rotor tip geometries on aerodynamic performance and tip vortex characteristics

2018-09-05
Uluocak, Sinem
Hazaveh, Hooman Amiri
Perçin, Mustafa
Akpolat, M Tuğrul
Uzol, Oğuz
In this study, the effects of different tip geometries (rectangular, anhedral, swept-tapered and swept-tapered-anhedral) on the rotor hover performance and tip vortex characteristics are investigated experimentally. A scaled rotor model set-up, instrumented with thrust and torque sensors, is used for aerodynamic performance measurements in hover and a two-dimensional (2D) particle image velocimetry (PIV) is used to obtain the tip vortex characteristics such as vortex trajectory, maximum tangential velocity, and circulation. Although taper+swept and taper+swept+anhedral configurations have the best CT/CQ values at lower blade loadings, at higher blade loadings anhedral case has the best performance and an increase of 0.03 figure of merit compared to the baseline. It is observed that different tip shapes change the vortex trajectory, in addition, reduces maximum tangential velocity and circulation significantly. The PIV measurements which were performed at a high blade loading show that there is a correlation between the aerodynamic performance and the vortex strength.
44th European Rotorcraft Forum 2018, ERF 2018; (18 September 2018 through 21 September 2018)

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Citation Formats
S. Uluocak, H. A. Hazaveh, M. Perçin, M. T. Akpolat, and O. Uzol, “Experimental investigation of the effects of different helicopter rotor tip geometries on aerodynamic performance and tip vortex characteristics,” presented at the 44th European Rotorcraft Forum 2018, ERF 2018; (18 September 2018 through 21 September 2018), Delft, Netherlands, 2018, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/78260.