The effect of tip-shape modification on blade-vortex interaction-induced helicopter blade-slap noise was investigated. The general rotor model system (GRMS) with a 3.148 m (10.33 ft) diameter, four-bladed fully articulated rotor was installed in the Langley V/STOL wind tunnel. The tunnel was operated in the open-throat configuration with treatment to improve the semi-anechoic characteristics of the test chamber. Based on previous investigation, four promising tips (ogee, sub-wing, 60 deg swept-tapered, and end-plate) were used along with a standard square tip as a baseline configuration. Aerodynamic and acoustical data concerning the relative applicability of the various tip configurations for blade-slap noise reduction are presented without analysis or discussion.
An Experimental Investigation of the Effect of Rotor Tip Shape on Helicopter Blade-Slap Noise
1979
464 pages
Report
Keine Angabe
Englisch
Helicopter Noise Blade Slap. Part 2 Experimental Results
NTIS | 1972
|Helicopter noise - blade slap ; Pt. 2: Experimental results
TIBKAT | 1972
|Subjective evaluation of helicopter blade slap noise
NTRS | 1978
|