Experimental and Numerical Investigation on Hydrodynamic Response of Spar with Wind Turbine under Regular Waves

The necessity of offshore wind turbines to generate wind power is multifold and well known. The focus of offshore based wind farms are mainly due to abundant availability of unobstructed wind power and land use restriction. Therefore, the development of floating type supports for offshore wind turbines is getting more attention. In this paper the experimental and numerical investigation on the motion response of Spar supporting the wind turbine under regular waves is presented. The experiments were conducted in three stages viz. (a) Spar with stationary wind turbine under regular waves. b) Spar with rotating wind turbine under calm sea conditions. c) Spar with rotating turbine under regular waves. Numerical simulation of the Spar response due to incident waves and the wind turbine torque is carried out using AQWA software. The results obtained from experiments are then compared with that obtained from numerical analysis. The measured Response Amplitude Operator (RAO) compares well with that obtained from numerical analysis. The comparison of measured response and simulated response for wind turbine rotation case shows reasonable match. The combined effect of wind turbine rotation and incident wave on the hull response is 10%, 16% and 32% higher than that of the response due to incident wave alone for heave, surge and pitch responses respectively.