Damilola Oyejobi,
Volume 14, Issue 8 (12-2016)
Abstract
The occurrence of wave and wind forces on tension leg platform (TLP) was assumed to be statistically independent but the intensity of wave force is a function of wind velocity because wave is a wind driven force. The focus of this paper is to study the effects of wind velocity on wave force. The contribution of steady and fluctuating wind to the response of the TLP over random wave only was also studied. Pierson Moskowitz wave and Emil Simiu wind spectra are simulated using Monte Carlo simulation. The variable submergence, drag force in Morison equation, tension fluctuation together with coupling between wind and wave contributed to the non-linearity considered in the single degree of freedom equation. The dynamic equation was solved using Newmark-Beta scheme. The statistical and power spectral density functions of the response quantities are reported. It is concluded that wind forces reduce the root mean square (RMS) tension force in the cable and thereby increased the motion responses in intact and a removed tendon TLP. The wind driven force (wave) has higher responses in severe sea states and the contribution of wind effect was suppressed due to hydrodynamic damping. The effect of the wind fluctuation is more pronounced in less severe sea state.Stochastic response of intact and a removed tendon tension leg platform to wave and wind loads