SesamCAESESmaritime_2014

DNV GL © 2014 SAFER, SMARTER, GREENER DNV GL © 2013

Sesam CAESES

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Software for simulation-driven design

DNV GL © 2014

FRIENDSHIP SYSTEMS

Located in Berlin/Potsdam, Germany

Founded in 2001 as spin-off from TU Berlin

CAE software development and related

services

Products: CAESES / FRIENDSHIP-Framework

Since 2009: a GL Company

Since 2013: a DNV-GL Company

(Part of the DNV-GL Software Division)

- Over 17,000 employees in more than 85

nations

- Maritime and offshore

- Oil and gas

- Energy and sustainability

Main product

CAESES / FRIENDSHIP-Framework

DNV GL © 2014

Breaking the Rules to Unleash Design Innovation

For performance critical flow exposed

surfaces and products

– Conduct design explorations

– Formal optimization

CAESES is an Upfront CAE system

featuring

– Innovative tools and functionality

– Within highly automated

processes

– Providing high-fidelity variable

geometry

– In a single integrated user

interface

DNV GL © 2014

CAESES

Upfront Optimization

• Post-processing of large sets

• Design explorations

• Formal optimization

• Assessment tools

Upfront CAD

• Simulation-ready

• Variable geometry

• Pre-processing

• Highly automated

CAESES – Upfront CAE System Empowering Simulation

Variable

Geometry

Pre-

processing

Software

Connection

Post-

processing

Optimization &

Assessment

Upfront Simulation

• Modern architecture

• Fast, accurate, scalable

• Robust auto meshing

• Batch processing

Mesh

Generation Solver

DNV GL © 2014

Traditional CAD

Traditional Simulation

(for validation & verification only)

Upfront CAE

Upfront CAD

Upfront Simulation


Concept Initial Design Definition &

Development Detailed Design

Verification (digital & physical

prototype) Production

Upfront CAE with CAESES

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Maritime industry

Typical application

Geometric modeling and hydrodynamic optimization of hull

forms for best-in-class performance

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Offshore industry

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Typical application

Optimization for better seakeeping, e.g. reduced motions and accelerations

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Process Workflow: Setting up the Automation Chain

Variable

Geometry

Pre-

processing

Software

Connection

Post-

processing

Optimization &

Assessment

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Upfront CAD – Variable Geometry

High-fidelity modeling of complex free

formed surfaces

– Automated variable geometries

– Focus on models subject to internal or external

flows

– In particular, complex surfaces that are

traditionally difficult to parameterize

Simulation-ready CAD

– Based on in-house proprietary CAD kernel

– Right amount of detail at the right time

– Reduced degrees of freedom

Multiple strategies

– Fully-parametric “smart” models

– Partially-parametric models based on morphing

and deformation

– Parametric sensitivities for Adjoint methods

DNV GL © 2014

CAESES Meta-surface Technology

Profile defined using specialized curve types and controlled by user-defined parameters

Initial profile is transformed along a specified path, and its parameters are varied based on functional distributions

Proprietary curve-engine and meta-surface technology creates complex surfaces with intelligent parameterization

From 2D thinking to 3D high-fidelity models

DNV GL © 2014

1. 2D blade definition • NACA profile • Parameters: chord, thickness, camber, position

2. Radial distributions • 2D section parameters (chord, thickness, etc.) • 3D stacking parameters (pitch, rake, skew)

3. Surface generation • Single blade

Chord Thickness Pitch Rake Skew

x

Example: Propeller

4. Propeller • Parameters: blade number, hub radius

DNV GL © 2014

Example: Propeller – 1 model can create huge number of variants

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Upfront CAD – Smart Modeling

Superior geometric control

Excellent freedom & flexibility

High-fidelity guaranteed

Smart parametrics

– Reduced degrees of freedom

(DoF)

– Built-in constraints

Standard design: Design and optimize on 2D sections, then stack - Poor quality 3D shape - Many DoF - Takes long time

CAESES smart model: 3D blade designed and optimized directly - High quality blade - Reduced DoF - Fast process

Aeroengine Compressor Blade

Semi-submersible for Offshore Oil Built in constraints:

Pontoon shape variation for sea-keeping - Draft fixed - Displacement fixed * All designs are feasible

By courtesy of Rolls-Royce

DNV GL © 2014

By courtesy of FutureShip

Smart Modeling – Example

Cruise Ship Hull-form Variation - Center of buoyancy fixed - Displacement fixed - Degrees of freedom reduced

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Partially-Parametric Modeling

Shift strategies for transforming existing geometries

– Spot shifts for smooth Cartesian & radial

deformations

– Delta curve or surface to shift in the direction of

principal axes, according to a 1D or 2D function,

respectively

– Lackenby shift specifically for ship hull

modification

DNV GL © 2014

Upfront CAD – Pre-processing

Simulation-ready geometry

– Watertight

– User specified resolution

– Automatic adaptation for each variant

Exchange file formats

– NURBS surfaces / B-rep

– IGES, STEP, ACIS/SAT

– Discretized geometry STL (multiple

formats)

– Colored STL (e.g STAR-CCM+)

– Extracted colors (e.g. Xflow)

– Specialized formats

– For Numeca geomTurbo

– Propeller free format (PFF)

– Panel meshes for potential codes

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Software Connection – coupling to external CFD codes

Example: Mixing vessel study with coupling to STAR-CCM+

Geometry:

STL file

Control files:

Java macros, SIM file

Results values:

CSV files

Link to solver

Results files:

Screen shots, field data

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Post-Processing

• Result files from the CFD solver

– Images, convergence history, etc.

• Flow-field data can be loaded and

manipulated in CAESES

– Surface plots

– Plane cuts

– Streamlines

– Vector plots

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Design engines to vary the geometry

Sobol for design of experiments (DoE)

Single-/multi-objective optimization

SSH Resource Manager – HPC grid engine

Automatic reporting and statistical analysis;

includes design tables, spider-web, Pareto

frontier plots, etc.

Direct flow-field comparison of variants

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– Ducts, diffusers, and manifolds

– Turbomachinery blades and volutes

– Automotive components

– Aerodynamic or hydrodynamic

bodies

Variable Geometry Models | Examples

DNV GL © 2014

By courtesy of FutureShip

Hull-form Variation

Can dramatically reduce wave resistance

DNV GL © 2014

Wake Equalizing Duct

Improves wake homogeneity and propeller efficiency

DNV GL © 2014

Ship Hull and Twin Screw

Maintain watertight STL for all variants

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Fine-tuning of Appendages

For higher energy efficiency

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Propeller Boss Cap Fin

Watertight STL maintained while varying chord, span, pitch

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Tank Model

Maximize tank capacity via (internal) optimization

Collision and engine bulkhead constraints built in

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Floaters

Optimized for sea keeping

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Wind Turbine

With variable pitch blades

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Photo by courtesy of DSME

Resistance Optimization of a Container Carrier

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Phase 1

– Select proven parent ship

– Scale to principal

dimensions

– Undertake CFD simulations

for re-combinations of

various fore- and aftbodies

– Choose most promising

candidate as baseline for

systematic parameter study

Phase 2

– Investigate a series of variants by

means of parametric modeling

and CFD

– Identify influences of individual

form parameters

– Pick best hull form

– Conduct model tests

Old process

New process

Process Workflow

DNV GL © 2014

Source: DSME

Optimized design

Baseline

Design Comparison

DNV GL © 2014

Modifications undertaken

– CAESES’ generalized Lackenby

transformation

– Parallel mid-body

– Angles of SAC

– Volume distribution at FP

Improvements found

– Favorable propulsion

characteristics

– High robustness

– Reduced wave resistance

Source: HSVA Substantial gain in energy efficiency

Final design showed reduction of 50% in wave resistance

Systematic Parameter Study

DNV GL © 2014

Design speed

HSVA data base filter

CB [0.65, 0.70] LPP [300.0, 365.0] B [42.0, 52.0] Nprop = 1

( data made anonymous)

Comparison to Other Carriers

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Seakeeping Optimization of a Semi-Submersible

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DNV GL © 2014

Process Workflow: Setting up the Automation Chain

Variable

Geometry

Pre-

processing

Software

Connection

Post-

processing

Optimization &

Assessment

DNV GL © 2014

Upfront CAD: Variable Geometry

Parametric model

– Fully parametric surface model

of semi-submersible

– Two symmetry planes

– Constant displacement via

volume shifts when varying

parameters

– Topology may change (e.g.

disappearing surfaces)

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Upfront CAD: Pre-processing

Structured panel mesh used for

discretization

Parametric refinement for all

patches controlled by a single

parameter

Customized export using Sesam’s

proprietary FEM-format for smooth

data transfer

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DNV GL © 2014

Upfron Simulation: Software Connection

Intuitive set-up using CAESES’

Software Connector

Process chain connects

– HydroD

– PostResp

Compute semi-submersible’s worst

relative motion within a given sea

state (air gap)

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Upfront Optimization: Post-processing

RAOs

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Upfront Optimization: Optimization & Assessment

Design of Experiments

– Sobol

– 150 variants

Six free variables

Constraints

– Keep displacement

– Keep draft

Objective

– Find design with lowest

relative motion

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DNV GL © 2014

Improved design

Results

Reduction of relative motion by about 4% when compared to baseline

Decrease of wetted surface

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Baseline

DNV GL © 2014

Results

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Selected references

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DNV GL © 2014

I’m using CAESES for sailing yacht design. It makes the difference between guessing according to rules of thumb and knowing which design is better or: jumping from the middle ages to the 21st century.

Bodo Hasubek

If the hull is already optimized using CAESES it cannot be improved any further.

Cho Tae-Ik Executive Vice President

Customer testimonials

I have found CAESES to be an essential tool for high-fidelity modeling and optimization of centrifugal compressor volutes; no other software could give me such a powerful but easy-to-use tool for modeling such a complex geometry.

Elia Cipolato M.Eng, Research Engineer

Before introducing CAESES we ran about one hundred RANSE simulations per year. On the basis of CAESES we now undertake several ten thousands of viscous simulations every year. This gives us exceptional insight for key product decisions that we would not be able to generate without CAESES.

Michael Palm Head of Ship Hydrodynamics

In our experience, using CAESES for creating parametric models was MUCH faster and easier than with our traditional CAD tool. With CAESES we can now create all of the design candidates in hours instead of weeks! Pol Muller

Head of Thrusters

Getting technical support from FRIENDSHIP SYSTEMS feels like having an expert within my own team. Not only do I get fast professional responses to address my specific questions, but above and beyond that I’m given expert guidance of how to squeeze out the very best performance of my designs.

Mr. Qin Bingjun Assistant Managing Director

DNV GL © 2014

SAFER, SMARTER, GREENER

www.dnvgl.com

Thanks for Your Attention

Mike Saroch

[email protected]

+49-331-96766-0

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SesamCAESESmaritime_2014