Computational Simulation Of Horizontal Axis Wind Turbines Dynamics And External Flow

Wind turbine is a device for extracting energy from the wind. Modern wind turbine is made up of a complicated combination of components and sub-systems, main elements are rotor,tower,hub,nacelle,foundation,power train and control system. There is a trend towards large and flexible wind turbines which can capture as much as the available kinetic energy from wind for the lowest possible cost.Wind turbines often operate in a negative environment where strong flow fluctuations, due to the nature of the wind, can excite heavy loads. The varying loads, together with flexible structure, can induce structural vibration Some wind turbines were damaged by high speed wind. Hence, there is increasing need for computational and experimental procedures for wind-resistant analysis of wind turbine. The fundamental of the wind turbine wind-resistant analysis is structural dynamic analysis and external flow analysis.This paper mainly deals with two aspects:One aspect is structural dynamic characteristics analysis of rotor blade and wind turbine. Finite element models for simulation of the dynamic response of rotor blade and horizontal axis wind turbine has been developed. The simulations are performed using the commercial finite element software AYSYS, which is a program developed for versatile analysis, covering linear as well as non-linear, static as well as dynamic applications. Then the structural dynamic characteristics of rotor blade and wind turbine are studied.The other aspect is the CFD simulation of the external flow around wind turbine. Firstly, the fundamental mathematical and mechanical theories of Computational Fluid Dynamics (CFD) are introduced; secondly the characteristics of the commercial CFD software Fluent are outlined; Finally, the external flow of wind turbine are simulated using Fluent.The work of this paper can found a solid base for further wind resistant analysis of wind turbine.