Abstract
An experimental method to study helicopter blade–vortex interaction (BVI) noise has been developed. Called the blade-controlled disturbance interaction, the method nearly replicates a rotor BVI by having a single-bladed rotor pass through a stationary gust field specially designed to simulate the highly impulsive induced velocity field of a vortex. This approach can be used to evaluate the effectiveness of blade design changes to noise radiation during a BVI event, as well as to study the effect of different interaction geometries on the resulting noise. The first set of experiments in this facility shows that the directionality of BVI noise radiation is very sensitive to the interaction angle. Oblique interactions spread the acoustics energy over wider azimuth angles compared to parallel interactions, as well as move the peak noise location closer to the rotor plane. Linear two-dimensional unsteady aerodynamic theory predicts the overall directionality trends reasonably well. However, the actual pulse shapes do not match and noise levels are underpredicted, particularly for oblique interactions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
