MID-FIDELITY AEROACOUSTIC ANALYSIS OF A LIFT-OFFSET COAXIAL ROTOR IN FORWARD FLIGHT

S. C. Lee; Y. S. Lim; Y. S. Jung

doi:10.6112/kscfe.2026.31.3.039

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2026 Vol.31, Issue 3 Preview Page Next Page

Original Article

MID-FIDELITY AEROACOUSTIC ANALYSIS OF A LIFT-OFFSET COAXIAL ROTOR IN FORWARD FLIGHT 중 충실도 기반의 Lift-Offset 동축반전 로터의 전진 비행 공력 소음 해석

30 September 2026. pp. 39-59

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Abstract

This study established a mid-fidelity analysis framework by coupling a vortex particle method (VPM)-based aerodynamic solver with a comprehensive rotorcraft analysis code to investigate the aerodynamic and aeroacoustic characteristics of a coaxial lift-offset rotor system. Using the developed framework, the effects of rotor shaft tilt, lift offset, and flight speed on aerodynamic interactions and noise characteristics were analyzed. The results showed that variations in shaft tilt altered the aerodynamic load distribution and noise directivity, with aeroacoustic noise induced by inter-rotor interactions being particularly dominant. As the lift offset increased, the aerodynamic loading increased on the advancing side but decreased on the retreating side. Overall, higher lift-offset conditions reduced aeroacoustic noise in the forward region of the rotor disk and on the retreating side. As flight speed increased, the blade–vortex interaction (BVI) region shifted aft, and the intensity of aerodynamic load fluctuations increased. In particular, under the 200-knot condition, abrupt load fluctuations caused by BVI were identified as a primary contributor to high-frequency aeroacoustic noise. The developed framework demonstrated its ability to capture the complex aerodynamic interactions and aeroacoustic characteristics of coaxial rotor systems and is expected to serve as an efficient tool for evaluating rotor performance and noise during the preliminary design stage.

Keywords

회전익기(Rotorcraft)

동축반전로터(Coaxial rotor)

와류 입자법(VPM)

공력 소음(Aeroacoustics)

전진 비행(Forward flight)

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Information

Publisher :Korean Society for Computational Fluids Engineering
Publisher(Ko) :한국전산유체공학회
Journal Title :Journal of Computational Fluids Engineering
Journal Title(Ko) :한국전산유체공학회지
Volume : 31
No :3
Pages :39-59
Received Date : 2026-05-11
Revised Date : 2026-07-21
Accepted Date : 2026-07-21
DOI :https://doi.org/10.6112/kscfe.2026.31.3.039

Journal of Computational Fluids Engineering ISSN:1598-6071(Print) 3022-6252(Online) 한국전산유체공학회지

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