Marine Opera*ons Ship design group Ship mo*on models

Stability calcula*ons Wave-induced mo*on

analysis Seakeeping Operability

Propulsion Main propulsors Thrusters

Manoeuvering Standard manoeuvering tests Rudder models

Marine opera*ons LiAing opera*ons

Light liA Heavy liA

Hydrodynamic models Wire/cable/pipe Submerged object

Through splash zone and seabed proximity

DNV RP Marine Opera*ons Planning of marine

opera*ons Weather windows Short term sta*s*cs Long term sta*s*cs

Stability calcula+ons

'T'

R

GZ

1 rad

GZ = GM ( i rad)

GZ1()

GZ2() Effect of additional load, either AH wire or crane load. Reduced stability

Stability model Crane simulator

Wave-induced mo*on Seakeeping Operability Predic*on

Vessel data Hull lines Loading condi*on

Wave spectrum Model spectrum

(e.g. JONSWAP) Long-crested or short-crested

Sea-keeping criteria Wave scaRer diagram

Vessel mo*on characteris*cs Various headings Various speeds

Response spectrum Boundaries for operability Operability of vessel

Calculated

Specied by the user

Propeller models

Generic models Propulsion Thrusters

Computa*onal Fluid Dynamics

Detailed understanding of the ow condi*ons

Wake ow

Mo+on stability deni+ons Straight line stability or Dynamic stability

Direc+onal stability or Course stability Posi+onal mo+on stability or Path stability

Manoeuvering

Rudder forces

LiA and drag increase with increasing rudder angle

Why does a rudder stall?

Rudder Forces

Bulbous prole High stall High drag

Slim prole Low stall Low drag

Prole Shape

Propulsion eciency

Manoeuvrability

Installa*on of anchors

The AHV carries the anchor

The AHV pulls the mooring line away from the rig

May need assistance from another vessel to lower the anchor on loca*on

Anchorhandling operations Rig move

Catenary equations Drag force model submerged wire

Dynamics in liAing opera*ons The various phases during a liAing opera*ons

LiA-o (snatch loads) Through splash zone (slamming) Sea bed proximity eects

Light liAing opera*ons Sta*c congura*on Dynamics ver*cal and horizontal Heave compensa*on Hydrodynamics coecients for subsea modules

Heavy liAing opera*ons Mul*body dynamics

Calcula*on details can be found in DNV RP-H103 Modelling and analysis of marine opera+ons

Heavy liEs: Coupled dynamics, No heave compensa*on, Mul*body dynamics W > 1000 tonnes

Light liEs: Dynamics of vessel marginally aected of weight of load, Heave compensa*on possible, W < 100 tonnes

Five phases of crane opera*ons Some possible problems