Abstract
A new three-degree-of-freedom model simulating vortex-induced vibrations (VIVs) of turbine blades is proposed. Equations of motions include the coupling for bending and torsion of a blade as well as the fluid-blade interactions, which is described by a van der Pol oscillator. The 1:1 internal resonance analysis is carried out with the multiple scale method, and modulation equations are derived. Bifurcation curves for responses with respect to the detuning parameter and dimensionless freestream velocity are obtained. Effects of the system parameters including the lift and moment coefficients, structural damping, cubic nonlinearity and coupling parameters on the responses are investigated. It is found that dynamic behaviours such as the saddle-node and Hopf bifurcations can occur for certain values of the system parameters. The approximate solutions obtained by the multiple scale method are validated by a direct numerical simulation. The results indicate that the proposed three-degree-of-freedom model can be useful to explain the dynamic response characteristics of blades and to optimize the blade design.
| Original language | English |
|---|---|
| Pages (from-to) | 2607-2628 |
| Number of pages | 22 |
| Journal | Meccanica |
| Volume | 51 |
| Issue number | 11 |
| Early online date | 22 Feb 2016 |
| DOIs | |
| Publication status | Published - Nov 2016 |
Bibliographical note
AcknowledgmentsThe authors acknowledge the Project 11372082 supported by National Natural Science Foundation of China, the project 2015CB057405 sponsored by the National Basic Research Program of China and the State Scholarship Fund of CSC. D.W. thanks for the hospitality of University of Aberdeen.
Keywords
- Fluid-blade interactions
- Hopf bifurcation
- Internal resonance
- Saddle-node bifurcation
- van der Pol oscillator
- Vortex-induced vibration