سال انتشار: ۱۳۸۳

محل انتشار: ششمین همایش بین المللی سواحل، بنادر و سازه های دریایی

تعداد صفحات: ۵

نویسنده(ها):

Mahdi ShafeeFar – Professor Assistant of Hydraulic & Marine Engineering Group in Tarbiat Modarress University
Mahdi Adjami – Graduated Student of Marine Engineering Tarbiat Modarress University

چکیده:

An approximate method based on Morrison approach is developed and is applied to predict
the motion response of semi-submersible in oblique seas using small amplitude wave theory. The
velocity forces and moments have been shown to be small and are therefore neglected. The
damping coefficients are obtained from experimental results while added-mass is evaluated using
known experimental and theoretical data. Also the interference effects of the various volume
elements of the semi-submersible on the flow field are neglected. Comparison of this approximate
method shows quite a good agreement with those carried out by other researcher or softwares
except for pitch motion which gives a much higher prediction. Spectral analysis is discussed in
detail and is applied in predicting the short-term and long-term extreme motion response. The shortterm
extreme response is based on 50 and 100 years return design sea states while long-term
prediction is based on the anticipated life of the semi-submersible.