Numerical simulation and analysis of the vortex ring state boundaries of the Ka-62 helicopter main rotor

Article

Published: 24.01.2024

Authors: Makeev P.V., Ignatkin Yu.M., Shomov A.I., Selemenev S.V.

Published in issue: #1(145)/2024

DOI: 10.18698/2308-6033-2024-1-2330

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

The paper presents results of studying aerodynamic characteristics of the Ka-62 helicopter main rotor in the vortex ring states. A nonlinear bladed vortex rotor model developed at the Department of Helicopter Design of the Moscow Aviation Institute was used. The vertical and steep descent modes were considered for the main rotor angles of attack in the range of 90…30 degrees and vertical descent velocities of 0…30 m/s at the constant time-averaged value of the thrust coefficient of 0.015.. A large amount of data was obtained, including flow patterns around the main rotor, integral aerodynamic characteristics and nature of their alterations in various modes of the steep descent. Based on analyzing the obtained aerodynamic characteristics, boundaries of the vortex ring states were constructed in the Vx – Vy velocity coordinates using a complex that included a number of special criteria. The results obtained were compared with the available experimental data. Importance of studying the boundaries of the vortex ring state zone for specific propellers is demonstrated taking into account their individual characteristics. The results obtained significantly complement the existing experience of experimental and numerical research in this area.

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