In all but the floodable length and tank calibration analysis modes, Hydromax is capable of including the effects of user-defined damage. Hydromax allows the user to set up a number of damage cases. Volumes that are permanently flooded should be defined as non-buoyant volumes.

To add a damage case, make the Damage window active and select Add Damage Case from the Case menu. You may specify a name for the Damage Case in the dialog. Each new damage case will have a column in the Damage Window and a tick may be placed to indicate which tanks and compartments are damaged for that particular Damage Case. The new damage case is added after the currently selected damage case column, to insert a damage case immediately after the intact case, select the intact case column. Several damage cases may be added in one go by selecting a number of columns.

To delete damage cases, simply select the columns to be deleted in the Damage Window and select Delete Damage Case from the Case menu. Note that it is not possible to delete the intact case.

The name of the current damage case may be changed by selecting Edit Damage Case when the damage case window is active, the current damage case is selected from the Analysis toolbar – see below.

The current damage case is selected from the Analysis toolbar.

The Loadcase and View windows will reflect the damage defined in the current damage case. To perform analyses for the intact vessel, select Intact as the current damage case.

Any subsequent analyses will take into account the damaged compartments. Note that carrying out a Tank Calibration analysis will force the intact case to be selected. This is also the case for the Floodable Length analysis which effectively sets up its own longitudinal extent of damage.

When tanks have been damaged, their weights and levers are no longer displayed in the Loadcase window and the word ‘Damage’ is displayed in the quantity column. This is because Hydromax uses the “Lost buoyancy” method rather than “Added mass”.

Note:

Hydromax uses the “Lost buoyancy” method rather than “Added mass”.

Flooding is considered to be instantaneous up to sea level. Any tank fluids are treated as having been completely replaced by seawater up to the equilibrium waterline.

Hydromax assumes that all compartment definition has been done after the tanks have been defined. If you have linked tanks or compartments or added tanks within compartments after the definition of a damage case, you should toggle the damage status of the damaged tanks. This is simply done by copying all the damage case data to a spread sheet, turning off all damage in all the damage cases (use the fill down command) and then pasting back in the original data from where it was stored in the spreadsheet.

When a damage case is selected, all damaged tanks and compartments will be displayed in damaged tank or damaged compartment colour respectively. These colours can be specified in the View | Colour menu.

In the Loadcase Window damaged tanks are displayed with the label 'Damaged' in the Quantity column, and all values set to zero.

The Loadcase Window displays damaged tanks and excludes them from any calculations.