Dynamic Analysis of Offshore Wind Turbine Towers with Fixed Monopile Platform Using the Transfer Matrix Method

Abstract

In this paper, an analytical method for vibrations analysis of offshore wind turbine towers with fixed monopile platform is presented. For this purpose, various and the most general models including CS, DS and AF models are used for modeling of wind turbine foundation and axial force is modeled as a variable force as well. The required equations for determination of wind turbine tower response excited by the Morrison force are derived based on Airy wave theory. The transfer matrix is derived for each element of the tower using Euler-Bernoulli's beam differential equation and the global transfer matrix is obtained considering boundary conditions of the tower and constructing the point matrix. The effective wave force is intended in several case studies and Persian Gulf Environmental conditions are examined for the installation of wind farms. Finally, the obtained results by the transfer matrix method are compared with the results of the finite elements method and experimental data which show good agreement in spite of low computational cost.