Aeroacoustics source mechanisms of fixed-wing VTOL configuration

Paruchuri, Chaitanya; Pallejà Cabré, Sergi; Joseph, Phillip; Akiwate, Deepak; Westcott, Oliver; Ferraro, Mario

Abstract

This paper is a predominantly experimental investigation into the noise generation mechanisms of Fixed-wing Vertical Take-Off and Landing (VTOL) propeller – wing configurations. These new aircraft combine the benefits of being able to land vertically in urban areas while being able to fly like conventional propeller-driven aircraft. However, their unique arrangement of wing and propeller that can rotate relative to the wing leads to aeroacoustic source mechanisms that have never, or are poorly, understood. During forward flight the aeroacoustic mechanisms of propeller-wing interaction have been studied theoretically and experimentally in recent work. However, during transition, and particularly during vertical takeoff, the flow from the propeller is incident upon the wing at high incidence angle, leading to new source mechanisms and balance of sources. This paper reports the results of acoustic and velocity measurements of a scale-model propeller adjacent to a flat plate or wing for the purpose of identifying and characterising the dominant noise generation mechanisms of propeller -wing interaction. In this paper we focus on the hover condition and investigate the variation in noise due to the vertical separation distance and horizontal offset distance. The paper will demonstrate that the overall noise is the summation of the noise due to the interaction of the tip vortex of the propeller with the wing leading edge, rotor-alone noise, potential field interactions at close separation distance, turbulent-wing interaction at larger separation distance, and the interference effects due to reflections from the wing. The balance of these various sources with vertical and horizontal separation distance is explored.

• Presentation Conference Type: Conference Paper (published)
• Conference Name: AIAA AVIATION 2023 Forum
• Start Date: Jun 12, 2023
• End Date: Jun 16, 2023
• Publication Date: Jun 8, 2023
• Deposit Date: Feb 5, 2025
• Journal: AIAA AVIATION 2023 Forum Proceedings
• Peer Reviewed: Not Peer Reviewed
• DOI: https://doi.org/10.2514/6.2023-3356