Hydromax is a hydrostatics, stability and longitudinal strength program specifically designed to work with Maxsurf. Hydromax adds extra information to the Maxsurf surface model. This includes: compartments and key points such as downflooding points and margin line.
Hydromax’ analysis tools enable a wide range of hydrostatic and stability characteristics to be determined for your Maxsurf design. A number of environmental setting options and modifiers add further analysis capabilities to Hydromax.
Hydromax is designed in a logical manner, which makes it easy to use. The following steps are followed when performing an analysis:
§ Input model
§ Analysis type selection
§ Analysis settings
§ Environment options
§ Criteria specification and selection
§ Run analysis
§ Output
Hydromax operates in the same graphical environment as Maxsurf; the model can be displayed using hull contour lines, rendering or transparent rendering. This allows visual checking of compartments and shows the orientation of the vessel during analysis.
Maxsurf design files may be opened directly into Hydromax, eliminating the need for time-consuming digitising of drawings or hand typing of offsets. This direct transfer preserves the three-dimensional accuracy of the Maxsurf model.
Tanks can be defined and calibrated for capacity, centre of gravity and free surface moment. Tanks and compartments can be flooded for the purpose of calculating the effects of damage.
A number of loadcases can be created. The loadcase allows static weights and tank-fillings to be specified and calculates the corresponding weights and centres of gravity as well as the total weight and centre of gravity of the vessel under the specified loading condition.
Other input consists of: tank sounding pipes; key points, such as downflooding points, immersion and embarkation points; margin lines and section modulus.
Hydromax contains the following analysis tools:
§ Upright hydrostatics
§ Large angle stability
§ Equilibrium analysis
§ Specified Condition analysis
§ KN values and cross curves of stability
§ Limiting KG analysis
§ Floodable Length analysis
§ Longitudinal Strength analysis
§ Tank Calibrations
Although common analysis settings are used where possible, different analyses may require different settings. For example: the upright hydrostatics analysis simply requires a range of drafts; whereas the longitudinal strength analysis requires a detailed load distribution. The analysis settings for each analysis type are explained in detail in the analysis synopsis below.
The analysis settings describe the condition of the vessel to be tested. For example, a range of drafts in the case of upright hydrostatics, or a range of heel angles for a large angle stability analysis.
The following analysis settings are available:
§ Heel
§ Trim
§ Draft
§ Displacement
§ Permeability
§ Specified conditions
The analysis settings are specified prior to running the analysis. Settings that are not relevant to the selected analysis type are greyed out in the Analysis menu.
Environmental options are modifiers that may be applied to the model or its environment that will affect the results of the hydrostatic analysis.
Depending on the analysis being performed, different environmental options may be applied to the Hydromax:
§ Type of Fluid Simulation
§ Density (of fluids)
§ Wave forms
§ Grounding
§ Hogging and sagging
§ Intact and Damage condition
Hydromax has the capability to calculate compliance with a wide range of stability criteria. These criteria are either derived from the properties of the stability curve calculated from a Large Angle Stability analysis or from the vessel’s orientation and stability properties calculated from an Equilibrium analysis. Limiting KG and Floodable length analyses also use stability criteria.
Hydromax has an extensive range of stability criteria to determine compliance with a wide range of international stability regulations. In addition, Hydromax has a generic set of parent criteria from which virtually any stability criterion can be customized.
Views of the hull are shown for each stage of the analysis, complete with immersed sectional areas and actual waterlines. The centres of flotation, gravity and buoyancy are also displayed. Heeled and trimmed hullforms and water plane shapes may be printed.
Results are stored and may be reviewed at any time, either in tabular form, or as graphs of the various parameters across the full range of calculation. All results are accumulated in the Report window (which can be saved, copied and printed), or output directly to a Word document.
The criteria checks are summarised in tables listing the status (pass/fail) of each criterion. The criterion settings and intermediate calculation data may also be displayed if required.
For a brief overview of the different analysis that Hydromax has available, continue reading Chapter 2 Quickstart.