Aeroelastic Responses of Ultra Large Wind Turbine Tower-Blade Coupled Structures with SSI Effect

Abstract

By a case study on a new-generation 5MW ultra large wind turbine system, the finite element model of the blade-nacelle-tower-foundation coupled structure with soil-structure interaction (SSI) and blade rotational centrifugal force is established. The harmonic superposition method and modified blade-element momentum theory are used to predict the aerodynamic loads with the consideration of tower-blade aerodynamic and model interaction, and modification of steady wind. Then the modal superposition method is adopted to solve the wind turbine coupling dynamic equation, in which the blade speed and aerodynamic force were updated though iteration to obtain the aeroelastic loads. At last, based on the previous work of “consistent coupling method”, which can fully consider the structure background mode, resonant mode, and the coupling effect between them, the aeroelastic responses of the wind turbine-blade coupled system are investigated. For completeness, the action mechanism of SSI effect and aeroelastic effect on the wind-induced responses are discussed through parameter analysis. The research conclusions can provide a scientific foundation for wind-resistance design of the ultra large wind turbine systems.