This paper presents an approach to compute fluid-structure interactions on wind turbines. It is a contribution to the development of future design tools and aims to improve the quality of numerical simulations of the fluid-structure interaction process, leading to a better understanding of the underlying physics. The presented approach is widely discussed in literature and is referred to as tight or strong coupling.
Strong coupling means an exchange of fluid loads and structural deformations at each time step. Since the analysis methods and codes for both domains have independently reached a high level of sophistication, this approach is effectuated in a fully modular manner and data is exchanged between separate codes. The underlying coupling schemes are classified by the character of time integration on fluid and structure side, respectively. Several combinations are possible, but this paper focuses on a first order implicit-explicit scheme.
So far the strong coupling focuses on rotor only computations. The respective models on both fluid and structure side are presented and discussed. The contribution presents coupled fluid-structure computations at the rotor of a 2.75 MW wind turbine. The results are compared to and validated against state of the art simulation tools.