Dynamic vibrations in wind energy systems: Application to vertical axis wind turbine

• Published in: Mechanical systems and signal processing Vol. 85; pp. 396 - 414
• Main Authors: Mabrouk, Imen Bel, El Hami, Abdelkhalak, Walha, Lassâad, Zghal, Bacem, Haddar, Mohamed
• Format: Journal Article
• Language: English
• Published: Berlin Elsevier Ltd 15-02-2017; Elsevier BV
• Subjects: Aerodynamic loads; Aerodynamic torque; Aerodynamics; Bevel spur gear; Computational Fluid Dynamic; Computational fluid dynamics; Darrieus wind turbine; Dynamic vibration; Fluid dynamics; Fluid flow; Frequency domain analysis; Incompressible flow; Navy; Non-stationary regime; Shear stress; Spur gears; Stiffness; Tip speed; Torque; Turbines; Turbulence; Turbulence models; Two dimensional models; Vertical axis wind turbines; Vibration; Wind power; Wind turbines; Bevel spur gear; Computational Fluid Dynamic; Darrieus wind turbine; Aerodynamic torque; Non-stationary regime; Dynamic vibration
• ISSN: 0888-3270; 1096-1216
• DOI: 10.1016/j.ymssp.2016.08.034

Dynamic analysis of Darrieus turbine bevel spur gear subjected to transient aerodynamic loads is carried out in the present study. The aerodynamic torque is obtained by solving the two dimensional unsteady incompressible Navies Stocks equation with the k–ω shear stress transport turbulence model. The results are presented for several values of tip speed ratio. The two-dimensional Computational Fluid Dynamics model is validated with experimental results. The optimum tip speed ratio is achieved, giving the best overall performance.
In this study, we developed a lamped mass dynamic model with 14 degrees of freedom. This model is excited by external and internal issues sources. The main factors of these excitations are the periodic fluctuations of the gear meshes' stiffness and the unsteady aerodynamic torque oscillations. The vibration responses are obtained in time and frequency domains. The originality of our work is the correlation between the complexity of the aerodynamic phenomenon and the non-stationary dynamics vibration of the mechanical gearing system.
The effect of the rotational speed on the dynamic behavior of the Darrieus turbine is also discussed. The present study shows that the variation of rotor rotational speed directly affects the torque production. However, there is a small change in the dynamic vibration of the studied gearing system.
•Study of a bevel gear dynamic behavior in non-stationary regime is investigated.•2D CFD model is validated with experimental results to introduce the transient aerodynamic load.•The influence of rotating speed on the Darrieus turbine dynamic behavior is obtained.•The rotational speed affects significantly the aerodynamic performance.•The best performance according to power production and bearing vibration was achieved.