Hits:

Indexed by:期刊论文

Date of Publication:2012-10-15

Journal:OCEAN ENGINEERING

Included Journals:SCIE、EI、Scopus

Volume:53

Page Number:25-37

ISSN No.:0029-8018

Key Words:QTF; Slow drift force; Low-frequency; Irregular waves

Abstract:In this paper, the classical free surface integral formula is examined by an analysis based on the development of the free surface forcing term in a power expansion with respect to Delta omega. The zero order contribution to the infinite integration which produces the corresponding load of first order Delta omega) is formulated. Then a novel approach which can be easily implemented for predicting the low-frequency QTF is proposed. By applying higher order BEM and adaptive method in element integration, a numerical program is developed. The developed program is tested on simple geometric bodies and offshore platforms. The results from the present study agree well with the results of available exact solutions. Time domain simulation and spectral analyses of the slow drift force are performed for typical kinds of platforms. Extensive discussions and comparisons of the results based on the present method, Teng's exact method and widely used Newman's approximation are presented. The effectiveness of the proposed novel method is further demonstrated by these comparisons. (c) 2012 Elsevier Ltd. All rights reserved.