Dynamic response analysis of a combined wave and wind energy platform under different mooring configuration

Abstract

In the present study, a novel concept of combining a submerged tension leg platform (STLP) with six heaving type point absorbers WEC in circular pattern is presented for different mooring configurations. The tensioned tendons are used to fix the floating combined wave and wind energy system in position. The safety, stability and power production of the combined floating platform depends significantly on the integrity of the tendons. The combined wind and wave platform supported by four, five, eight and nine tendons are analysed for the operating conditions of the 5MW wind turbine under regular waves. Time domain numerical simulation tool FAST developed by NREL is used to perform the aero-servo-hydro-elastic simulation. The spectra of surge, sway, roll, pitch and yaw motion of the combined system under each mooring configuration is presented to analyze the behavior of the combined wave and wind energy system. Statistical results on the tension developed on each tendon for different mooring configurations is also presented to study the importance of mooring and the influence of mooring system on the dynamic responses of the combined floater. The study performed will be helpful in the design and analysis of possible configurations of mooring lines supporting the floating platform and improving the structural integrity of the combined floating concept.