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Title: Floating body second order slow drift force spectrum

Abstract

In this paper it is shown that the slow drift force spectrum of a floating body, obtained from the quadratic transfer function, can be approximated, in the range of interest ({mu} {much_lt} 1) by a white noise of the form S{sub F}({mu}) = S{sub F}(0) + O({mu}{sup 2}) where S{sub F}(0) can be computed from the known drift force coefficient in harmonic waves and the wave energy spectrum. It is also shown here that a special and normally used form of Newman`s approximation represents the spectrum S{sub F}({mu}) with an error [1 + O({mu}{sup 2})] in the low frequency regime. It is also shown that a well chosen Newman`s Approximations may be O({mu}{sup 2}) instead of only O({mu}).

Authors:
 [1];  [2]
+ Show Author Affiliations
  1. Univ. of Sao Paulo (Brazil). Dept. of Naval Architecture and Ocean Engineering
  2. PETROBRAS, E and P/GETINP/GESEM, Rio de Janeiro (Brazil)
Publication Date:
OSTI Identifier:
449688
Report Number(s):
CONF-9606279-
ISBN 0-7918-1490-4; TRN: IM9714%%245
Resource Type:
Conference
Resource Relation:
Conference: 14. international conference on offshore mechanics arctic engineering (OMAE), Florence (Italy), 16-20 Jun 1996; Other Information: PBD: 1996; Related Information: Is Part Of Proceedings of the 15. international conference on offshore mechanics and arctic engineering -- OMAE 1996. Volume 1, Part A: Offshore technology; Chakrabarti, S.K. [ed.] [Chicago Bridge and Iron Technical Services Co., Plainfield, IL (United States)]; Pontes, M.T. [ed.] [Inst. Nacional de Engenharia e Tecnologia Industrial, Lisbon (Portugal)]; Maeda, Hisaaki [ed.] [Univ. of Tokyo (Japan)]; Falzarano, J. [ed.] [Univ. of New Orleans, LA (United States)]; Schofield, P. [ed.] [W.S. Atkins, Surrey (United Kingdom)]; Morrison, D. [ed.] [Shell E and P Technology Co., Houston, TX (United States)]; PB: 530 p.
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; OFFSHORE PLATFORMS; ENERGY SPECTRA; WAVE FORCES; FLUID-STRUCTURE INTERACTIONS; WATER WAVES; HYDRODYNAMICS; TRANSFER FUNCTIONS

Citation Formats

Aranha, J.A.P., and Fernandes, A.C.. Floating body second order slow drift force spectrum. United States: N. p., 1996. Web.
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Aranha, J.A.P., & Fernandes, A.C.. Floating body second order slow drift force spectrum. United States.
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Aranha, J.A.P., and Fernandes, A.C.. Tue . "Floating body second order slow drift force spectrum". United States. doi:.
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@article{osti_449688,
title = {Floating body second order slow drift force spectrum},
author = {Aranha, J.A.P. and Fernandes, A.C.},
abstractNote = {In this paper it is shown that the slow drift force spectrum of a floating body, obtained from the quadratic transfer function, can be approximated, in the range of interest ({mu} {much_lt} 1) by a white noise of the form S{sub F}({mu}) = S{sub F}(0) + O({mu}{sup 2}) where S{sub F}(0) can be computed from the known drift force coefficient in harmonic waves and the wave energy spectrum. It is also shown here that a special and normally used form of Newman`s approximation represents the spectrum S{sub F}({mu}) with an error [1 + O({mu}{sup 2})] in the low frequency regime. It is also shown that a well chosen Newman`s Approximations may be O({mu}{sup 2}) instead of only O({mu}).},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Dec 31 00:00:00 EST 1996},
month = {Tue Dec 31 00:00:00 EST 1996}
}
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