KDS Offshore
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Capability · 01 / 09 · Naval architecture

3D Geometrical Modelling

Watertight surfaces, ready for class.

Lead time · 2–4 weeksFixed-fee, fixed-scopePrincipal-ledAuthor · Sérgio Ribeiro e Silva, PhDLast reviewed ·
✦ TL;DR

3D geometrical modelling is the production of watertight, parametric CAD surfaces that feed every downstream marine engineering task — structural FEA, CFD, mooring analysis, and class-society review — from a single source of truth. KDS Offshore builds models in Rhino + Grasshopper compliant with STANAG 4684 conventions, then hands over native, STEP, IGES, and section exports.

Overview

What this service is

Every project we run starts from a single source of truth: the geometry. We build watertight, parametric surface models that downstream FEA, CFD, mooring, and class-society reviews can all read without re-meshing.

Our models follow Simulation-Based Design and Virtual Prototyping (SBDVP) principles, including the HLA conventions defined by STANAG 4684 ("On Virtual Ships") so that the same geometry can drive a stability calculation in Maxsurf, a CFD run in STAR-CCM+ or OpenFOAM, and a class-society submission to DNV, BV, RINA, or Lloyd's Register.

We deliver clean topology, frame and section exports, and visualisation-ready renders. The model is yours; we hand over the file, not just the answer.

See our methods →

Outcomes

Numbers we expect to defend

100%
watertight on handover
automated manifold-check on every delivery
0
geometry rework after class review
SeaPower 12 m pilot boat, OneOcean working boat
2–4 wk
turnaround on a typical 15–30 m hull
from lines plan to handover
STANAG 4684
compliant by default
HLA conventions on every parametric model
Deliverables

What you get

01
Production CAD
02
Closed surface model
03
Geometric plan export
04
Drawings for class-society approval
05
Visualisation renders
06
Documented topology & parameters
Fit

When this is the right call

✓ When to use
  • A new hull, novel concept, or unusual deckhouse where no existing geometry is reliable.
  • Multiple downstream uses planned: CFD + FEA + stability + visualisation — one model serves all.
  • A class submission is on the critical path and the geometry must pass DNV / BV / RINA / LR review without rework.
  • You expect to iterate (move the deckhouse aft, change the appendage, re-distribute tankage) over the next 12 months.
✗ When not to use
  • A solid IGES already exists, has been through class, and no further parametric variation is planned.
  • A 2D plan is sufficient (single drawing for permitting), with no downstream analysis attached.
Methodology

How we run a project

  1. 01 / 04

    Geometry brief

    Lines plan, principal particulars, intended downstream use (CFD, FEA, classification, marketing), and target tolerances.

  2. 02 / 04

    Surface build

    Parametric surface model in Rhino + Grasshopper, with named control sections, watertight checks, and version control.

  3. 03 / 04

    Downstream sanity checks

    Quick CFD or stability run to verify the model behaves before we hand it over.

  4. 04 / 04

    Handover

    Native + STEP/IGES + section exports, with a one-page README explaining the parametric controls.

Tools & methods

Software stack we use

  • Rhino + Grasshopper
  • Maxsurf
  • AutoCAD
  • STEP / IGES interchange
  • STAR-CCM+ (downstream CFD)
  • OpenFOAM (downstream CFD)
Regulatory context

Frameworks we help you satisfy

  • STANAG 4684NATO standard for virtual ships; HLA conventions adopted throughout.
  • DNV class-society geometry conventionsWatertight, manifold, named control sections.
  • Bureau Veritas Marine NR467Hull-form definition requirements for steel-ship submissions.
  • RINA — Rules for the Classification of ShipsGeometric inputs to scantling and stability rule checks.
  • Lloyd's Register — Rules for the Classification of ShipsCompatible parametric topology, named sections.
Vessel types

Where this discipline applies

  • Pilot boats, fast craft, RIBs
  • Working boats and supply vessels
  • Offshore platforms, semisubmersibles, FPSO topsides
  • Wave-energy converters, floating wind sub-structures
  • Patrol and naval craft
  • Yachts and tourism vessels
Selected work

Where this discipline was used

·01OneOcean working boatOneOcean2021↗·02SeaPower 12 m pilot boatSeaPower2022↗
Common questions

FAQ

What does "watertight" actually mean in your deliverable?

Closed surface, no boundary edges, manifold topology, suitable for downstream CFD meshing or FEA without manual repair. We run an automated check before handover and document any tolerances.

Will the model survive a class-society review?

Yes. We build to the geometry conventions DNV, BV, RINA, and Lloyd's Register expect, and we have a track record of submissions that pass without geometry rework.

Do you keep the model alive after delivery?

On request. Most clients return six months later with a "what if we move the deckhouse aft?" question, and the parametric model lets us answer in days, not weeks.

Other capabilities

Eight other disciplines, one office

✦ Brief this service · 3D modelling

Tell us about the vessel.

A 30-minute call with a principal. No deck, no sales engineer. Two engineers, your problem, an honest answer about whether KDS is the right firm.

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