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

SesamTM for offshore wind

DNV GL © 2013

Offshore wind – combining DNV GL competencies

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= +

40+ years of offshore oil

& gas experience

Global leader in risk

management of

offshore wind projects

DNV GL has 25 years

of hands-on experience

with wind turbines.

DNV GL Software

provides 40+ years of

offshore oil & gas

experience.

DNV GL © 2013

SesamTM – a 40 years success story

A complete system for strength assessment and sea-keeping analysis of ship and offshore structures

Used to design ships, offshore fixed and floating structures from shallow waters to ultra deep waters in harsh environments as well as structures supporting wind turbines

Covers the range from FEED to field abandonment and forms the basis for reanalysis systems in the operational phase

Documents a safe structure satisfying design standards, statutory regulations and criteria for HSE – covers the range from stress evaluations to code checking and fatigue of plates and beams

More than 170 organisations use Sesam as their preferred tool for structural engineering

GeniE for structural analysis

HydroD for hydrostatics and dynamics

DeepC for SURF, mooring and marine operations

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DNV GL © 2013

Sesam Wind Modules

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Fatigue Manager • FLS

Sesam Modules used:

• Wajac (hydrodynamics) • Sestra (solver)

• Splice (pile/soil)

• Framework (fatigue calculations)

GeniE • Modelling • ULS • Code-check

Sesam Modules used:

• Wajac (hydrodynamics) • Sestra (solver)

• Splice (pile/soil)

DNV GL © 2013

Sesam for other offshore wind related structural analysis

Design and analysis of

installation vessels

Transportation analysis

– Seakeeping and hydrodynamics

– Hydrostatics and stability

Installation analysis

– Lifting operations

– Through surface effects

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DNV GL © 2013

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Sesam for Fixed substructures

DNV GL © 2013

What can Sesam do for Offshore Wind Turbine Installations?

Design of substructures according to IEC61400-3 /DNV-OS-J101

Modelling

– Full 3D modelling environment for frame and shell models

– Consider complex transition structure between the wind tower and the supporting structure

Non-linear structural dynamics of fully integrated system

– Coupled analysis with Wind Turbine

– FE-representation of component

– Pile/Soil

– Wave-structure interaction

Structural assessment

– Eigenvalue analysis

– Calculation of beam forces and stresses

– Fatigue calculations

– Integrated code-check supporting NORSOK,API, AISC, Eurocode, ISO, DS

Floating Offshore Wind Turbine

– Simulate offshore wind turbines mounted on arbitrary floaters

– Interaction effects between - and dynamic responses of - all components

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DNV GL © 2013

Fatigue Manager (Uncoupled)

Time series of loads

at interface point.

Converters from:

– Bladed

– HAWC

.wind format

– Simple text file.

– time Fx Fy Fz Mx My

Mz

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DNV GL © 2013

Jacket, tripod and monopile

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1. Modelling and wave

load calculation Sesam GeniE

2. Wind turbine

design analysis (Bladed, HAWC,

FLEX, …)

3. Substructure and

foundation analysis - FLS Sesam Wind

- ULS Sesam GeniE

Load calculations Wind turbine design Substructure design

Load time

series Properties

Loads

DNV GL © 2013

Sesam Wind - Fatigue Manager imports Bladed Results

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Bladed

.$25 files with

Beam Forces and Moments

Fatigue

Manager Bladed Converter

_R1.SIN files

with structure and results

Use in Fatigue

Manager for FLS

or in GeniE for

Code-check

DNV GL © 2013

Fatigue

Methodology according to DNV-OS-J101 and DNV-

RP-C203

– Time-series simulation of wind/wave load

combinations

– Fatigue calculations by rainflow counting

– Pre-defined or user defined S-N curves and SCFs

Combined fatigue damage from all wind speed and

sea states

– Multiple wind speeds and sea states

– Multiple wind and wave headings

– Aligned and unaligned wind and sea

Printable report for overall results

Support for beam structures,…

– Circumferential and axial welds

– Tubular joints

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DNV GL © 2013

Fatigue Manager and Sesam Cloud

Faster

More complex structures

More load combinations

More design iterations

CPU capacity on demand

Data storage on demand

Data security

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DNV GL © 2013

Ultimate Strength and Code Check

Code check of beams and joints

according to international standards

– Eurocode

– NORSOK

– AISC

– API

Wind and Wave load combination by

– Characteristic loads

or

– Time series simulation

Graphical result presentation

Reporting

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DNV GL © 2013

Gravity based substructure

Base shear and overturning moment

from time series simulation of wave

loads and imported wind loads

Modelling

– Full 3D modelling environment for frame

and shell models

Loads

– Wave and current loads for slender and

large volume structures

– Random sea states and non-linear wave

– Hydrostatic and Froude-Krylov pressure

on exact wetted surface

– Import of wind loads (time series) from

wind turbine programs

Structural analysis

– Load transfer to structural model

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DNV GL © 2013

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How can Sesam help you to design floating OWT?

DNV GL © 2013

Sima for floating foundation and marine operations

Sima

– Coupled analysis of floating wind turbines

– Simulate OWT mounted on arbitrary

floaters

– Interaction effects between - and dynamic

responses of all components

–Dynamic equilibrium at each time step

ensured by direct nonlinear time domain

integration scheme

–Wave load and motion analysis

– Structural analysis

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DNV GL © 2013

SIMA/RIFLEX – model for floating wind turbine

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Non-linear FE-model of entire system:

• Floater: hydrodynamic loads (1st and 2nd order potential wave forces, viscous drag)

• Mooring lines: hydrodynamic loads (generalized Morison load model)

• Tower: wind loads

• All the components: inertia forces, weight and buoyancy.

• Blades: Aerodynamic loads. BEM method (with dynamic inflow) on each element.

• Tower upwind effect on wind field by potential theory approach

• Control system: Blade pitch and electrical torque control algorithms

DNV GL © 2013

SAFER, SMARTER, GREENER

www.dnvgl.com

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