Operators Instructions Hydrostatics

AVEVA Initial Design Hydrostatics (in this manual referred to as Calc) is part of the integrated AVEVA Marine suite of programs, and its purpose of is to calculate hydrostatic, stability and other naval architectural calculations for a ship, and to document these for approval by statutory authorities and for use onboard. The output is typically a so-called Trim and Stability book.

Note:
AVEVA Initial Design Hydrostatics is later in this manual referred to as Calc.

Geometry Data

Geometry data is the basis of most calculations and with the aim of providing you with more options and greater flexibility, Calc can now utilize several alternative definitions and file formats for compartment geometry, as listed in the following table:

The Initial Design Geometry file conforms to the international XML standard and is the preferred method of transferring geometry and other fixed data between Initial Design modules. This file can store all supported types of compartment data, together with other data such as openings, deck edge and profile points, compartment categories, etc.

Section data is a popular method of defining hull forms in many programs, and Calc can now use this type of data, as an alternative to the standard facetted representation. The integration method for section data employs a Gaussian (or Simpson's) type procedure.

If the geometry of a compartment is not available, then a calibration table listing volumetric properties against tank soundings, can be used. A typical use would be where new loading conditions need to be added to the trim and stability book of an existing ship, but the original lines, are not available. Also small tanks could be defined using a calibration table, instead of having to model the tank, thus saving time. To obtain the volume properties at a given level, Calc simply interpolates in the calibration table.

The ability to import an SFOLDS Geometry Definition Store (GDS) file, has always been possible, but Calc versions 4 to M1 version 2 would transform the data to a facetted representation on input. This, however, generally creates a large volume of data. From Calc M1 version 3, portions are no longer transformed, but handled in the same way as in SFOLDS and early versions of Calc. The main advantage is that file sizes are smaller. Theoretically calculation speed should be also better, but this is not so marked. However, it should be stressed that the GDS file should be considered obsolete, and only retained for backwards compatibility with SFOLDS and earlier versions of Hydrostatics.

The new Calc Geometry XML file, can store all supported types of compartment data, together with other data such as openings, deck edge and profile points, compartment categories, etc. It conforms to the international XML standard, and is the preferred file format for importing and exporting geometry data to Hydrostatics. Surface/Compartment can export this file.

Refer to Initial Design Geometry XML File format for a description of the XML file format.

Graphical User Interface

The Calc User Interface makes use of dockable windows and toolbars. The following windows are dockable and can be hidden by you, if not required:

The Loading Diagram window, displays a 2D tank plan, which you can customise. Clicking on a compartment in this view, will bring up the compartment loading particulars, in the Associated dialog box, which can then be edited. This provides an Interactive Loading function as described below.

The operation of Calc can be controlled using a script in either Javascript or VBScript. The Script window provides the access to this function.

When Calc is closed, the docking state and size of the windows, are remembered.

Interactive Loading

To use the Interactive Loading facility, you should display the Loading Diagram window and open the Interactive Loading dialog by clicking on the Interactive Loading button on the Loading diagram toolbar, as shown in the following figure.

The loading group to be edited, should be selected in the dialog. Clicking on a compartment with the left-hand mouse button, causes its loading and other data, to be displayed in the dialog. you can then change the loading of the compartment by entering appropriate values, or by clicking the Fill or Empty buttons. The compartment description and category can also be changed. When the Apply button is clicked, any changes will be made and the Loading Diagram updated.

The dialog also has a Tank Plan Views tab, that allows you to modify the Tank Plan, i.e. views can be added, deleted or modified.

Licensing

With the inclusion of the hydrodynamic (Hydrodynamics) modules in Calc, a new scheme for handling licensing within the program, has been devised, which has the following features:

• you can select which license features he wishes to check out.

• Reports associated with a feature that is not checked out, can be viewed, but creating, editing and calculations, will be disabled.

• If any licence is checked out, then global data, including geometry, can be imported, modified, etc.

• If no licence is checked out, the project can only be viewed. Data cannot be edited, and calculations cannot be performed.

If, for example, a company has just one license for Hydrostatics and one for Powering, then it is possible for one person to use Calc for hydrostatics, and another to use it for powering calculations, provided that each person has just the one licence checked out.