Engineering Journal: Science and InnovationELECTRONIC SCIENCE AND ENGINEERING PUBLICATION
Certificate of Registration Media number Эл #ФС77-53688 of 17 April 2013. ISSN 2308-6033. DOI 10.18698/2308-6033
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Article

The effects of blade twist and swept surface load on the main rotor aerodynamic characteristics in the vortex ring state modes

Published: 02.07.2024

Authors: Makeev P.V.

Published in issue: #7(151)/2024

DOI: 10.18698/2308-6033-2024-7-2370

Category: Aviation and Rocket-Space Engineering | Chapter: Aerodynamics and Heat Transfer Processes in Aircrafts

The paper presents results of parametric studies of the geometric layout (blade twist) and the swept surface load on the main rotor (MR) aerodynamic characteristics and the vortex ring state boundaries. It considers the MR vertical descent in the 0–26 m/s speed range with the fixed blade installation angle. The research was carried out based on the nonlinear bladed vortex rotor model developed at the Department of Helicopter Design of the Moscow Aviation Institute. The model was validated using data from the well-known Washizu & Azuma experiments. Parametric studies examined 16 MR models with various combinations of blade twist and swept surface load (in hover). It was established that the considered parameters were significantly influencing the MR aerodynamic characteristics and the vortex ring state boundaries, including those boundaries constructed in the descent dimensionless relative speed. The conclusions drawn make it possible to explain differences in the vortex ring state boundaries constructed in the relative coordinates and observed in the experimental studies, linking them with the rotor parameters. Thus, comprehensive consideration of the rotor blade twist and the swept surface load is required in analyzing the helicopter rotor vortex ring state boundaries.

EDN RIPEOA


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