Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
DYNAMIC ANALYSIS OF WIND TURBINE TOWERS UNDER RANDOM WIND LOADING
Submission Author:
Dodani Renan de Morais , RS
Co-Authors:
Lucas Foschiera, Herbert Gomes, Dodani Renan de Morais
Presenter: Herbert Gomes
doi://10.26678/ABCM.COBEM2019.COB2019-0088
Abstract
This work proposes a methodology to evaluate the dynamic behavior over time of wind turbine towers taking into account the effects of wind on its structural components (tower, nacelle, and blades). A model of generation of wind velocity signals correlated in time and space is adopted, following a usual von Karman Power Spectral Density which has parameters such as turbulence intensities and standard deviations of the wind speed fluctuations in the three directions, velocity profile with height, and decay coefficients of the coherence with the distance between the points of wind action. It is investigated whether the time domain or frequency domain analysis are adequate in terms of simulation time, accuracy and computational costs for the evaluation of RMS values of acceleration and displacement signals at specific points of the wind turbine as well as base reactions. Three-dimensional beam type finite elements are used to obtain loads such as shear, bending moments and torsion. The Newmark Method for integration is used in time domain simulations. In the frequency domain, the direct integration of specific power spectral densities (displacements, accelerations, etc.) by the trapezoidal rule is employed. Results for a typical simulation are investigated and compared in different situations of wind speed and wind parameters for the simulation of the dynamic behavior of the structure. The obtained results present similarities regarding natural frequencies, main modes of vibration and vibration magnitude with cases reported in the literature.
Keywords
wind turbines, Newmark method, frequency domain analysis, correlated wind field generation
