2012 ANSYS, Inc. 1

ANSYS CFD for Naval Applications

Stephan Eder

stephan.eder@ansys.com

2012 ANSYS, Inc. 2

ANSYS CFD for Naval Applications

Preprocessing Geometry Meshing

Solver AQWA CFX Fluent System Coupling

Mechanical Electronic

Postprocessing

Design Exploration Parameters Optimization Six Sigma Adjoint Solver

2012 ANSYS, Inc. 3

ANSYS Geometry Tools

ANSYS Design Modeler Import external geometries Sketching functionality Direct body creation Multiple body operations Fluid volume extraction Geometry clean-up tools Analysis tools

ANSYS Space Claim Direct modeler Pull, move, fill and combine

tools

Parameters without constraints

2012 ANSYS, Inc. 4

Geometry Interfaces

Associative Interfaces

(Associative, bidirectional

and parametric)

Creo Parametric Creo Elements/Pro Creo Elements/Direct

Modeling

Inventor SolidWorks Solid Edge CATIA Teamcenter

CAD Readers

AutoCAD* Creo Elements/Pro NX Inventor SolidWorks Catia IGES and STEP Parasolid ACIS GAMBIT

* Requires an AutoCAD installation

Geometry Interfaces

2012 ANSYS, Inc. 5

ANSYS Meshing Tools

ANSYS Workbench Meshing Hexa meshing Mesh sweeping Prism-Tetra meshing Cut-Cell meshing Global and local mesh sizings Size functions Quality checks Mesh improvment

ANSYS ICEM Key feature:

Blockstructured hexahedral meshing

ANSYS Fluent Meshing Key features:

Surface wrapping Advanced hexcore meshing Advanced cut-cell meshing Parallel meshing

2012 ANSYS, Inc. 6

Mesh Topologies

Hex

ahe

dra

l me

sh

Hyb

rid

me

sh

Hex

core

me

sh

Cu

tce

ll m

esh

2012 ANSYS, Inc. 7

Mesh Topologies

Hex

ahe

dra

l me

sh

Hyb

rid

me

sh

Hex

core

me

sh

Cu

tce

ll m

esh

2012 ANSYS, Inc. 8

ANSYS CFD - Solvers

AQWA Potential flow solver Multi-body Hydrodynamic

and Motion Analysis

CFX/Fluent: Finite volume solver Pressure-based solver Density based solver

2012 ANSYS, Inc. 9

ANSYS AQWA

ANSYS AQWATM Fully Integrated Multi-body

Hydrodynamic and Motion

Analysis

Mooring, stability, vessel motions in regular and

irregular waves

within time and frequency domain

with coupled cable dynamics

with forward speed

Courtesy of PI-RAUMA Ltd.

2012 ANSYS, Inc. 10

ANSYS AQWA

Offshore Structures Fixed

JACKETS Concrete

Compliant Jack-ups

Floating Floating Production, Storage and

Offloading unit (FPSOs)

SPARS Semi-Submersibles Tension leg platforms (TLPs)

Risers

Ships Design Offloading

Harbours

2012 ANSYS, Inc. 11

ship & landing craft jacket launch shielding

lifting operation AMOG line Breakage mooring systems FSO and SPM with shuttle tanker

self-installing platform Arup Energy

transportation stinger cargo lowered onto vessel offloading operation SBM

ANSYS AQWA

2012 ANSYS, Inc. 12

ANSYS AQWA Capabilities

Diffraction/Radiation including Morison elements

Frequency domain analysis

Stability including mooring lines

Time domain with irregular waves

Time domain with non-linear survival waves

Coupled cable dynamics

Multiple hydrodynamic interaction and articulations (up to 50 structures)

Transfer of motions and pressures to ASAS & ANSYS FE models

2012 ANSYS, Inc. 13

ANSYS AQWA Modeling

Capabilities Diffracting or non-diffracting panels Morison elements

TUBE STUB DISC

Point masses Mixed models Moorings

Linear springs Elastic catenaries Intermediate buoys Tethers Pulleys

Fenders Articulations

2012 ANSYS, Inc. 14

ANSYS AQWA Modeling

Environment Waves

Regular / irregular Time history

Wave Spectra Pierson-Moskowitz JONSWAP User-defined Cross-swell

Current Uniform Profile

Wind Uniform Spectra Time history

2012 ANSYS, Inc. 15

ANSYS CFD

ANSYS CFD offers special marine related

tools:

Open (wave) channel flow

Compressible liquids Implicit six degree of

freedom solver

Wide range of dynamic mesh

capabilities

Slu

ice

liftin

g (

Co

urt

esy o

f B

un

de

sa

nsta

lt f

r W

asse

rba

u)

2012 ANSYS, Inc. 16

ANSYS CFD

Wave regimes First order Airy wave

theory

Stokes wave theories Cnoidal & Solitary Wave Superposition

Standing wave

Beats or wave groups

Constructive and destructive interference

Irregular waves

2012 ANSYS, Inc. 17

ANSYS CFD

and a lot more Single-/multiphase Cavitation Acoustics Energy/radiation/solar

load

Species transport/ chemical reactions

Turbulence Particle Flows (Discrete

phase/Discrete element/MPM)

Additional Input via user

programming

Climatisation of a Separator Room

(Courtesy of Flensburger Schiffbau-

Gesellschaft (Flensburg Shipyard))

Smoke from a large

production deck pool fire

(Courtesy of Daewoo

Shipbuilding)

Propeller Cavitation

(Courtesy SVA-Potsdam

(Potsdam Model Basin))

2012 ANSYS, Inc. 18

ANSYS CFD

Mesh motion: Automatic mesh adaption Tetra/cut-cell:

Smoothing

Remeshing

Hexa/prism: Smoothing

Layering

Six degree of freedom + implicit 6DOF

Immersed solid

Slu

ice lifting (

Court

esy o

f B

undesansta

lt fr

Wasserb

au)

2012 ANSYS, Inc. 19

ANSYS CFD

Optimizer & mesh morpher: User defined objective

function

User defined deforming

Objective Function: Uniform flow at

the outlet

Baseline Design

Optimized Design

Objective function: Max. lift

2012 ANSYS, Inc. 20

ANSYS CFD

Fluent Adjoint solver Submarine example:

Submarine drag optimization

Sensitivity plots

Geometry deformation

35 % drag reduction within 25 optimization loops

2012 ANSYS, Inc. 21

ANSYS CFD

Numerical Towing Tank ANSYS Workbench Geometry

Import geometry in Design Modeler

Define global geometry parameters Automatic domain creation

Meshing Automatic import into Meshing

Define global meshing parameters Automatic mesh creation

Solver Automatic import into the Solver

Define boundary conditions Calculate

Post-Processing Automatic import into CFD-Post

Examine results

2012 ANSYS, Inc. 22

ANSYS CFD

System Coupling Multiphysics coupling Structural mechanics Heat transfer Fluid flow Electromagnetics

2012 ANSYS, Inc. 23

Thank you for your attention