Question:

What is the best way to add a superstructure to a hull model to calculate
buoyancy and the effect of flooding?


Answer:

If you want to see the buoyancy contribution of the superstructure in
the STATUS reports, you should make it a separate part.  The class can
be SUPER.

If you want the buoyancy of the superstructure to be combined with the
HULL, you should make it a component of the HULL part.  For example,

  CREATE HULL\SUPER
    LOCUS ...
    ...
    FIT HULL.C

In order to study the flooding of the superstructure, you need to make
"tanks" within it.  For example,

  CREATE ROOM1.C
    ENDS 100, 150
    FIT HULL\SUPER.C
    CONTENTS SW

To study the effect of partial flooding in ROOM1, you will need to keep
it as an INTACT tank and load it with some amount of water.  For example,

  LOAD (ROOM1.C) = .1

If do not know the load fraction and want GHS to get it for you from a
water plane passing through a given point, set the Reference Point at
that point.  For example,

  HEEL=12
  TRIM=0
  TANK ROOM1.C
  REFPT= 120, -10, 20
  LOAD HEIGHT: 0

This will set the load fraction such that the water surface in ROOM1.C
passes through the given point when the heel is 12° to starboard and the
trim is zero.



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