Engineering Computations

Purpose – Wind turbines are of growing importance for the production of renewable energy. The kinetic energy of the blowing air induces a rotary motion and is thus converted into electricity. From the mechanical point of view the complex dynamics of wind turbines become a matter of interest for structural optimization and optimal control in order to improve stability and energy efficiency. The purpose of this paper therefore is to present a mechanical model of a three-blade wind turbine with a momentum and energy conserving time integration of the system.

Design/methodology/approach – The authors present a mechanical model based upon a rotationless formulation of rigid body dynamics coupled with flexible components. The resulting set of differential-algebraic equations will be solved by using energy-consistent time-stepping schemes. Rigid and orthotropic-elastic body models of a wind turbine show the robustness and accuracy of these schemes for the relevant problem.

Findings – Numerical studies prove that physically consistent time-stepping schemes provide reliable results, especially for hybrid wind turbine models.

Originality/value – The application of energy-consistent methods for time discretization is intended to provide computational robustness and to reduce the computational costs of the dynamical wind turbine systems. The model is aimed to give a first access into the investigation of fluid-structure interaction for wind turbines.