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 Israa Alesbe,Moustafa Abdel-Maksoud,Sattar Aljabair.Analysis of Unsteady Flow over Offshore Wind Turbines in Combination with Different types of Foundations[J].Journal of Marine Science and Application,2017,(2):199-207.[doi:10.1007/s11804-017-1414-x]
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Analysis of Unsteady Flow over Offshore Wind Turbines in Combination with Different types of Foundations


Analysis of Unsteady Flow over Offshore Wind Turbines in Combination with Different types of Foundations
Israa Alesbe12 Moustafa Abdel-Maksoud1 Sattar Aljabair12
Israa Alesbe12 Moustafa Abdel-Maksoud1 Sattar Aljabair12
1. Institute for Fluid Dynamics and Ship Theory (M8), Hamburg University of Technology (TUHH), D-21073 Hamburg, Germany;
2. Department of Mechanical Engineering, University of Technology, Baghdad 10066, Iraq
panel methodtime domainoffshore wind turbineRANSE solverboundary element methodunsteady flow
Environmental effects have an important influence on Offshore Wind Turbine (OWT) power generation efficiency and the structural stability of such turbines. In this study, we use an in-house Boundary Element (BEM)—panMARE code—to simulate the unsteady flow behavior of a full OWT with various combinations of aerodynamic and hydrodynamic loads in the time domain. This code is implemented to simulate potential flows for different applications and is based on a three-dimensional first-order panel method. Three different OWT configurations consisting of a generic 5?MW NREL rotor with three different types of foundations (Monopile, Tripod, and Jacket) are investigated. These three configurations are analyzed using the RANSE solver which is carried out using ANSYS CFX for validating the corresponding results. The simulations are performed under the same environmental atmospheric wind shear and rotor angular velocity, and the wave properties are wave height of 4?m and wave period of 7.16?s. In the present work, wave environmental effects were investigated firstly for the two solvers, and good agreement is achieved. Moreover, pressure distribution in each OWT case is presented, including detailed information about local flow fields. The time history of the forces at inflow direction and its moments around the mudline at each OWT part are presented in a dimensionless form with respect to the mean value of the last three loads and the moment amplitudes obtained from the BEM code, where the contribution of rotor force is lower in the tripod case and higher in the jacket case and the calculated hydrodynamic load that effect on jacket foundation type is lower than other two cases.


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Received date:2016-7-23;Accepted date:2016-11-18。
Corresponding author:Israa Alesbe, Email: israa.al@tuhh.de
Last Update: 2017-05-09