The Limiting KG analysis may be used to obtain the highest vertical position of the centre of gravity (maximum KG) for which the selected stability criteria are just passed. This may be done for a range of vessel displacements. At each of the specified displacements, Hydromax runs several Large Angle Stability analyses at different KGs. The selected stability criteria are evaluated; the centre of gravity is increased until one of the criteria fails.

Limiting KG Analysis Requirements

§   Range of displacements to be analysed

§   Range of heel angles to be analysed

§   Trim (fixed or free)

§   Stability criteria for which limiting KG is to be found

Limiting KG Analysis Options

§   Fluid Densities

§   Wave form

§   Hog and sag

§   Damage

§   Tank and Compartment definition (in case of damage)

§   Key points (if required for criteria)

§   Margin line and deck edge (if required for criteria)

A graph of maximum permissible GZ plotted against vessel displacement is produced as well as tabulated results indicating which stability criteria limited the VCG. If limiting curves are required for each of the stability criteria individually, this may be done in the Batch Analysis mode.

A check will be made to ensure that any selected equilibrium criteria are passed, however at least one large angle stability criterion is required. Only relevant criteria will be used, i.e. if a damage case is chosen, only damage criteria will be evaluated; if the intact condition is used, only intact criteria will be evaluated. Some criteria, such as angle of maximum GZ, are very insensitive to VCG and may prevent the analysis converging. If the analysis is unable to converge for a certain displacement this will be noted and the next displacement tried.

For more detailed information see Limiting KG on page 78.