Direct Numerical Simulation of Aeroelastic Vibrations of a High-Aspect Rod for Modes Similar to Resonance Modes
S. V. Pogudalina, N. N. Fedorova
Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090, Russia
Keywords: aeroelasticity, conjugate problems, interaction of flows with structures, wind effects, numerical modeling, flow structure, vortex Karman track, resonance
Abstract
This study touches upon a numerical simulation of vibrations of an elastic rod whose height is significantly greater than the transverse dimension and which is installed perpendicular to the external flow and rigidly fixed to the substrate. Modeling is performed in the ANSYS software complex using bi-directional technology pairing. Eigen-frequencies and vibrations modes of the rod are calculated. The structure is analyzed and the features of the flow are described. The process of excitation of vibrations of an elastic rod under the action of an external flow is investigated and its stress-strain state is determined. The vibration modes in the direction of the incident flow and in the transverse direction are determined. It is shown that at close values of the first natural frequency and the frequency of vortices descent, the amplitude of the rod oscillations in the transverse direction sharply increases to a value approximately equal to 0.06 of the rod height, after which a self-oscillating mode is established with a constant amplitude in the transverse direction and variable amplitude in the direction of the incident flow.
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