A higher-order free-wake method for a helicopter rotor in forward flight using distributed vorticity elements

Tenzin Choephel, Mark D. Maughmer

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The wake has a strong influence on the aerodynamics of a helicopter rotor operating in various flight modes. An accurate prediction of its geometry is critical for an improved understanding of aerodynamic performance, vibration and acoustics characteristics. In this paper, a higher-order lifting-surface method is discussed that uses singularity elements having distributed vorticity to model the lifting surfaces and shed wakes, and applies it to the problem of computing the free-wake geometry of a helicopter rotor in forward flight. Such distributed vorticity elements allow the representation of a force-free wake-vortex sheet that does not suffer from numerical singularities and is numerically robust with regard to the wake roll-up behavior. In contrast with other free-wake methods that use discrete vortex filaments, the new method does not require the implementation of vortex core models etc. Using this new method, the distorted wake geometry of a rotor in forward flight are computed, along with the capability of accounting for the effect of inboard active devices on wake development, airloads and downwash distribution.

Original languageEnglish (US)
Title of host publication70th American Helicopter Society International Annual Forum 2014
PublisherAmerican Helicopter Society
Pages2720-2728
Number of pages9
ISBN (Print)9781632666918
Publication statusPublished - Jan 1 2014
Event70th American Helicopter Society International Annual Forum 2014 - Montreal, QC, Canada
Duration: May 20 2014May 22 2014

Publication series

NameAnnual Forum Proceedings - AHS International
Volume4
ISSN (Print)1552-2938

Other

Other70th American Helicopter Society International Annual Forum 2014
CountryCanada
CityMontreal, QC
Period5/20/145/22/14

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Engineering(all)

Cite this

Choephel, T., & Maughmer, M. D. (2014). A higher-order free-wake method for a helicopter rotor in forward flight using distributed vorticity elements. In 70th American Helicopter Society International Annual Forum 2014 (pp. 2720-2728). (Annual Forum Proceedings - AHS International; Vol. 4). American Helicopter Society.