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Indexed by:期刊论文

Date of Publication:2016-09-01

Journal:JOURNAL OF SHIP RESEARCH

Included Journals:SCIE、EI、Scopus

Volume:60

Issue:3

Page Number:145-155

ISSN No.:0022-4502

Key Words:sandglass-type FPSO; cylindrical FPSO; deckwetness; second-order slowly varying loads

Abstract:In this paper, the influence of the second-order slowly varying loads on the estimation of deckwetness is studied. A series of experiments related to classic cylindrical and new sandglass-type Floating Production, Storage, and Offloading Unit (FPSO) models are conducted. Due to the distinctive configuration design, the sandglass-type FPSO model exhibits more excellent deckwetness performance than the cylindrical one in irregular waves. Based on wave potential theory, the first-order wave loads and the full quadratic transfer functions of second-order slowly varying loads are obtained by the frequency-domain numerical boundary element method. On this basis, the traditional spectral analysis only accounting for the first-order wave loads and time-domain numerical simulation considering both the first-order wave loads and nonlinear second-order slowly varying wave loads are employed to predict the numbers of occurrence of deckwetness per hour of the two floating models, respectively. By comparing the results of the two methods with experimental data, the shortcomings of traditional method based on linear response theory emerge and it is of great significance to consider the second-order slowly drift motion response in the analysis of deckwetness of the new sandglass-type FPSO.