Time-Domain Approach for Acoustic Scattering of Rotorcraft Noise

$30.00 plus tax (Refund Policy)

Buy Article:

Abstract:

This paper addresses acoustic scattering of rotorcraft noise in the time domain. A time-domain equivalent source method is used since it is considered to be a computationally efficient method to solve acoustic scattering. In addition, the time-domain method provides a solution for all frequencies of interest in a single computation and is able to predict the acoustic scattering of aperiodic signals. The prediction is validated against exact solutions for a monopole source. The numerical method is then used to predict acoustic scattering of noise from a BO105 tail rotor by a representative fuselage. Complex directivity patterns are seen in the near field, and a large scattering effect is observed in the far field to the side of the fuselage. The time-domain code results of sound pressure level are validated against the results obtained by a frequency-domain analysis. Finally, acoustic scattering for an impulsive noise source is investigated to simulate main rotor blade–vortex interaction noise. The scattered pressure has a comparable amplitude as that of the incident pressure so that the total pressure is dramatically changed compared to the incident pressure. For the impulsive noise, a large computational time saving is achieved compared to the frequency-domain approach, in which the computation must be repeated for each frequency.

Document Type: Research Article

DOI: http://dx.doi.org/10.4050/JAHS.57.042001

Publication date: October 1, 2012

More about this publication?
  • The Journal of the American Helicopter Society is the world's only scientific journal dedicated to vertical flight technology. It is a peer-reviewed technical journal published quarterly by AHS International and presents innovative papers covering the state-of-the-art in all disciplines of rotorcraft design, research and development. (Please note that AHS members receive significant discounts on articles and subscriptions.)

    Journal subscribers who are AHS members log in here if you are not already logged in.

    Authors can find submission guidelines and related information on the AHS website.

Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more