OPTNAV: Hull modeling and optimization made simple

OptNav is a multipurpose optimization tool for the hull designer. It combines different solvers such as Hydrostatics, Holltrop Resistance, Intact Stability Check, with a powerful modelling and deformation engine. These different features are orchestrated to generate precise design of experiments (DOEs) with automatic mesh generation of modified hulls, and pre-evaluation of hull performances.

Fast hull pre-design optimization, easy integration in your process

Hull optimization is the main way to meet environmental and cost-reduction challenges when designing or refitting a ship.

OptNav is an efficient pre-optimization tool based on a set of solvers and an innovative parametric hull modeler. OptNav helps the designer with its easy-to-use interface, by generating a complete set of computed data, CADs and meshes.

Hull efficiency is automatically evaluated through empirical resistance solvers, to allow the designer to identify the best hull design.

Thanks to its mesh binding and CAD export functionalities, OptNav easily integrates with your optimization process, by providing the adequate inputs for your CFD solution.

Features

Hydrostatics/Balance computation

OptNav provides a full set of hydrostatic parameters (up to 36), for both original and varied hulls
Different loading cases are possible :imposed position / imposed trim, heel and displacement (free in sinkage) / imposed displacement and mass center (free in sinkage, trim and heel)

Sectional area curves analysis and visualization

OptNav computes instantaneously section area curves

Intact stability evaluation

For a selected range of heel angles, the Gz value is calculated with a loop to identify hydrostatic equilibrium at fixed heel

Holltrop resistance computation

OptNav implements Holtrop Mennen empiric resistance computation
The following members are evaluated: wave resistance, friction resistance, roughness resistance, bulbous resistance, transom resistance, total resistance, specific resistance (resistance vs. displacement ratio)

Parametric deformations and DOE generation

Manage multiple deformations
Generate varied meshes, CADs

Characteristics

OptNav is a Robert McNeel & Associates Rhinoceros 3D plugin, for hull optimization, including all needed functionalities for the designer:

Hydrostatics computation
Sectional area curves
Intact static stability checks (Gz curves)
Holltrop resistance estimation

Analytic Bezier deformations and Grasshopper integration
CAD export (.3dm .step and .iges)
Automatic and parametric deformation cases and associated hydrostatics
Design Of Experiment generation (Sweeper), integrating Sobol distribution law, with comparison report
Surface mesh export: (Siemens STAR-CCM+, REVA, ISIS-CFD/NUMECA International FINE/Marine, REVA)
Volume mesh generation (Siemens STAR-CCM+, ECN-BEC ICARE)