Non-linear frequency-domain analysis of jack-up platforms

Numerical Analysis of Hydrodynamic Characteristics for Various Types of Jack-up Legs

“…Jack-up leg의 파랑중 비선형 운동 응답의 정확한 산정 방법 (Williams et al, 1998;Cassidy, 1999;Zheng and Liaw, 2004 (Dawson, 1983).…”

Frequency-domain analysis of non-linear wave effects on offshore platform responses

“…The non-Gaussian nature of the structural response of slender fixed offshore platforms has been extensively reported for many years and it was revealed that response non-Gaussianity is mainly attributable to the well-known non-linear drag term of Morison force [1][2][3][4][5][6] and varying water surface induced inundation effect [7][8][9][10]. In the absence of current, the drag nonlinearity results in odd-order super-harmonic phenomena, while the inundation effect leads to even-order super-harmonics [2,9].…”

“…In time domain, people most often rely on Monte Carlo simulation which, however, has been proved to be timeconsuming in numerical computation even if the water particle kinematics could be adequately modeled as Gaussian random processes in the case of a linear wave field [6,10,13]. After all, the convergence of higher-order statistics costs considerable computation efforts.…”

“…The early application of cubicization method to the square-law operation of Morison drag force can be found in Bendat and Piersol [17]. Similar works utilizing drag cubicization to estimate the response of offshore platforms in Gaussian sea conditions were available in [4,5,10,18,19].…”

“…To preclude the complexity induced by non-linear Morison drag force and inundation load in the frequency-domain analyses, polynomial expansions based on least squares [1,2,4,19] and moment-based [5,[9][10][11][12]20] schemes have been proposed. In this study, the moment-based approximation (MBA) will be applied to precisely capture the statistical moments of wave force and structural response in non-Gaussian seas.…”