Akademik Veri Yönetim Sistemi
Gemi ve Deniz Teknolojisi Dergisi, sa.219, ss.107-123, 2021 (Hakemli Dergi)
Among all ship motions, the most critical one is
the roll motion for a submarine. The excessive roll motion can be harmful to
both ship's crew and equipment, especially in surfaced condition. For this
reason, it is important to predict the roll motion during the design stage to
overcome excessive roll amplitudes. A mathematical model of the roll motion can
be used to predict the motion responses of a submarine. Estimation of the roll
damping is the most critical part to develop the mathematical model for a
better prediction of the roll motion. The roll damping can be obtained
experimentally, numerically and empirically. Experimental methods are expensive
and time-consuming and empirical methods cannot be applied for all ship types.
For this reason, numerical methods are frequently used due to the development
of computer technologies in recent years, being economical and fast. In this
study, the mathematical model of roll decay motion for a submarine at surfaced
condition was obtained. The roll damping term was obtained numerically by
carrying out roll decay simulations using a commercial Computational Fluid
Dynamic (CFD) code. The inertia and restoring terms were obtained empirically
by using the submarine geometry. The mathematical model was obtained and the
roll decay motion of the surfaced submarine was calculated with a 20 degrees
initial roll angle at zero speed and 5 kn, 7.5 kn and 10 kn forward speeds. The
results were compared with numerical results and a good agreement was observed.