The development of offshore wind farms for deep water has inspired the design of various deepwater floaters that could survive harsher environments. Among the proposed designs, spar-type wind turbine designs appear to be a very promising concept. During the preliminary design stage, numerical tools that can be used to quickly estimate the hydrodynamic and aerodynamic response of the floating system with a good accuracy has been the subject of much research. In 2014, a model test was conducted in the State Key Lab of Ocean Engineering (SKLOE) at Shanghai Jiao Tong University. A 1:50 scale model of the NREL (National Renewable Energy Lab) 5MW baseline wind turbine atop the OC3-Hywind spar-buoy was tested for a design water depth of 200 m. The present research study explores the accuracy of numerical predictions based upon the use of the industry-standard software packages OrcaFlex and second order WAMIT codes in comparison with the measurements from a recent experimental study. This approach allows the consideration of nonlinear wave and wind loadings on the moored Spar wind turbine platform system. A comparison between numerical calculation by presented tool and the experimental data provided by SKLOE shows a good agreement.
During the past several decades, offshore oil and gas resources have been sought globally to meet the sharply increasing demand of energy. At the same time, the huge emission of greenhouse gas as well as other relevant environment problems sets off the alarm that some environmental friendly renewable energy should take the place of traditional fossil fuel resources. The conversion of the global wind resource and its potential to provide electrical power have been effectively demonstrated by the continued development of relatively near shore wind farms on a global scale. The challenge is to develop floating wind turbine designs for deepwater offshore wind farm sites that will survive extreme environment events.
