Page 291 - Practical Design Ships and Floating Structures

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Length of machinery space
Height of main deck above keel

The first should be as large as possible and the second should be as low as possible to lower the centre
of gravity and to reduce the steel weight. In the sensitivity studies dealing with these parameters it is
important to account for their influences on other parameters. In the present analyses the centre of
gravity, the steel weight, the position of the vehicle deck and the down-flooding points are adjusted for
changes in the distance H, measured from the tank top to the main deck. The length of the machinery
space is supposed not to alter other pertinent parameters than the subdivision. The results from the sen-
sitivity study are given in Figures 4 and 5. The vessel is the same as in the previous chapter but below
the main deck it is divided into three main compartments. The machinery space is in the middle placed
symmetrically with respect to midship. The layout is hence in between layouts #3 and #4.

Figure 4: Attained Index A as a fhction of length L of machinery space and height H from tank top to
main deck. SOLAS Part B-1

Figure 5: Attained Index A as a fhction of length L of machinery space and height H from tank top to
main deck. SLF 431312