Numerical and experimental analysis of extreme wave induced vertical bending moments on a FPSO

Fonseca, Nuno; Pascoal, Ricardo; Soares, C. Guedes; Clauss, Günther F.; Schmittner, Christian E.

doi:10.1016/j.apor.2010.08.001

Cited by 31 publications

(9 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the potentially severe damage from extreme waves to the vessels and offshore structures at sea Fonseca et al, 2010), a lot of efforts have been devoted to the topic of the mechanisms of their generation. A number of reasons why freak wave phenomena may occur have been explained.…”

Section: H D Zhang Et Al: Modeling Extreme Wave Heights From Labormentioning

confidence: 99%

Modeling extreme wave heights from laboratory experiments with the nonlinear Schrödinger equation

Zhang¹,

Soares²,

Cherneva³

et al. 2014

Nat. Hazards Earth Syst. Sci.

Self Cite

View full text Add to dashboard Cite

Abstract. Spatial variation of nonlinear wave groups with different initial envelope shapes is theoretically studied first, confirming that the simplest nonlinear theoretical model is capable of describing the evolution of propagating wave packets in deep water. Moreover, three groups of laboratory experiments run in the wave basin of CEHIPAR (Canal de Experiencias Hidrodinámicas de El Pardo, known also as El Pardo Model Basin) was founded in 1928 by the Spanish Navy. are systematically compared with the numerical simulations of the nonlinear Schrödinger equation. Although a little overestimation is detected, especially in the set of experiments characterized by higher initial wave steepness, the numerical simulation still displays a high degree of agreement with the laboratory experiments. Therefore, the nonlinear Schrödinger equation catches the essential characteristics of the extreme waves and provides an important physical insight into their generation. The modulation instability, resulting from the quasi-resonant four-wave interaction in a unidirectional sea state, can be indicated by the coefficient of kurtosis, which shows an appreciable correlation with the extreme wave height and hence is used in the modified Edgeworth-Rayleigh distribution. Finally, some statistical properties on the maximum wave heights in different sea states have been related with the initial Benjamin-Feir index.

show abstract

Section: H D Zhang Et Al: Modeling Extreme Wave Heights From Labormentioning

confidence: 99%

Modeling extreme wave heights from laboratory experiments with the nonlinear Schrödinger equation

Zhang¹,

Soares²,

Cherneva³

et al. 2014

Nat. Hazards Earth Syst. Sci.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Much interest has been recently directed towards understanding of the observed extreme waves with relatively low probabilities of occurrence in view of their effect on ships (Guedes Soares et al, 2008) and offshore structures (Fonseca et al, 2010). In this respect, controlled model tests in a laboratory are useful in studying the characteristics of waves that rarely occur at sea and the corresponding responses of marine structures, which can be used to validate the codes for calculating ship responses.…”

Section: Introductionmentioning

confidence: 99%

Distributions of nonlinear wave amplitudes and heights from laboratory generated following and crossing bimodal seas

Petrova

Soares

2014

Nat. Hazards Earth Syst. Sci.

Self Cite

View full text Add to dashboard Cite

Abstract. This paper presents an analysis of the distributions of nonlinear crests, troughs and heights of deep water waves from mixed following sea states generated mechanically in an offshore basin and compares with previous results for mixed crossing seas from the same experiment. The random signals at the wavemaker in both types of mixed seas are characterized by bimodal spectra following the model of Guedes Soares (1984). In agreement with the Benjamin-Feir mechanism, the high-frequency spectrum shows a decrease in the peak magnitude and downshift of the peak with the distance, as well as reduction of the tail. The observed statistics and probabilistic distributions exhibit, in general, increasing effects of third-order nonlinearity with the distance from the wavemaker. However, this effect is less pronounced in the wave systems with two following wave trains than in the crossing seas, given that they have identical initial characteristics of the bimodal spectra. The relevance of third-order effects due to free modes only is demonstrated and assessed by excluding the vertically asymmetric distortions induced by bound wave effects of second and third order. The fact that for records characterized by relatively large coefficient of kurtosis, the empirical distributions for the non-skewed profiles continue deviating from the linear predictions, corroborate the relevance of free wave interactions and thus the need of using higher-order models for the description of wave data.

show abstract

“…Regarding the present application, we made a Experimentally, the freeboard exceedance has been measured over the deck of simplified structures at positions very close to the deck edge (e.g., [1]). However, in more complex arrangements, such as ship-type structures, it has been necessary to install the wave probes outside the hull to monitor the relative deck-wave motions (e.g., [42,[45][46][47][48]). Details of the exact location of the wave probes with respect to the edge of the deck are scarce in most works.…”

Section: Freeboard Exceedancementioning

confidence: 99%

Green Water on A Fixed Structure Due to Incident Bores: Guidelines and Database for Model Validations Regarding Flow Evolution

Hernández-Fontes

Esperança

Bárcenas

et al. 2019

Water

View full text Add to dashboard Cite

This paper presents a two-dimensional experimental study of the interaction of wet dam-break bores with a fixed structure, regarding the evolution of the incident flows and the resultant green water events on the deck. The study employs image-based techniques to analyse flow propagation from videos taken by high-speed cameras, considering five different shipping water cases. The features of small air-cavities formed in some green water events of the plunging-dam-break type were analysed. Then, the spatial and temporal distribution of water elevations of the incident bores and green water were investigated, providing a database to be used for model validations. Some guidelines for the selection of the freeboard exceedance, which is of relevance for green water simulations, were provided. Finally, the relationship between the incident bore and water-on-deck kinematics was discussed. The proposed study can be used as a reference for performing simplified and systematic analyses of green water in a different two-dimensional setup, giving high-resolution data that visually capture the flow patterns and allow model validations to be performed.

show abstract

Numerical and experimental analysis of extreme wave induced vertical bending moments on a FPSO

Cited by 31 publications

References 30 publications

Modeling extreme wave heights from laboratory experiments with the nonlinear Schrödinger equation

Modeling extreme wave heights from laboratory experiments with the nonlinear Schrödinger equation

Distributions of nonlinear wave amplitudes and heights from laboratory generated following and crossing bimodal seas

Green Water on A Fixed Structure Due to Incident Bores: Guidelines and Database for Model Validations Regarding Flow Evolution

Contact Info

Product

Resources

About