Fan, X.; Liang, W.; Zeng, J.; Yang, Y.; Ma, H.; Fan, C.; Fu, S. Dynamic Characteristics of a Rotating Blade with a Dovetail Fixture. Machines2023, 11, 643.
Fan, X.; Liang, W.; Zeng, J.; Yang, Y.; Ma, H.; Fan, C.; Fu, S. Dynamic Characteristics of a Rotating Blade with a Dovetail Fixture. Machines 2023, 11, 643.
Fan, X.; Liang, W.; Zeng, J.; Yang, Y.; Ma, H.; Fan, C.; Fu, S. Dynamic Characteristics of a Rotating Blade with a Dovetail Fixture. Machines2023, 11, 643.
Fan, X.; Liang, W.; Zeng, J.; Yang, Y.; Ma, H.; Fan, C.; Fu, S. Dynamic Characteristics of a Rotating Blade with a Dovetail Fixture. Machines 2023, 11, 643.
Abstract
Considering rotation-induced centrifugal stiffening, spin softening, and Coriolis effects, the three-dimensional finite element model of a rotating blade with a dovetail structure is built through the contact dynamics theory. The fixed-interface component mode synthesis method is then adopted to reduce the model for high computational efficiency and adequate model accuracy. The effects of the number of normal modes on the first-six-order modal characteristics of the model varying with the rotating speed are studied between the reduced and full models. Next, the influence of rotating speed and friction factor on the nonlinear dynamic characteristics of the model under the action of aerodynamic force are elaborately discussed. The results show that: (1) tenon-mortise joint contact-induced nonlinearity under low rotating speeds results in the intermittent interference of contact surfaces and frequency multiplications of aerodynamic excitation frequency in the spectrum cascades, while that under high rotating speeds causes the continuous interface contact and asynchronous excitation at the tenon-mortise joint; (2) the increase of friction factor results in a lower contact pressure distribution and the right shift of the resonance peak (i.e., hard nonlinearity).
Keywords
rotating blade with a dovetail structure; fixed-interface component mode synthesis method; aerodynamic force; interface contact; dynamic characteristics
Subject
Engineering, Aerospace Engineering
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
