Presentation Friesch WG IMP 4th meeting 10 11 23
HydrodynamicOptimizationofShipsJ. FrieschHamburg Ship Model Basin23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 1Hydrodynamic Optimization– What can be gained?1. Introduction2. Optimal main dimensions3. Optimised hull form4. Hull surface resistance5. Propeller – rudder interaction6. Optimisation for service conditions7. Conclusions23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 2Hydrodynamic Optimization– What can be gained?23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 3Hydrodynamic Optimization– What can be gained?• Over 95% of World Trade is carried in ships• The vast majority of these ships are propelled byslow speed diesel engines – e.g. container shipsand oil tankers• The efficiency of these shipping operationsmeans that CO2 emissions per tonne/km are verylow• NOx and SOx emissions are legislated byMARPOL Annex VI and Flag States (e.g. EU)23.11.2010 FRIESCH Hydrodynamic Optimizsation of Ships BSPC 2010 4Hydrodynamic Optimization– What can be gained?23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 5Hydrodynamic Optimization– What can be gained?23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 6Hydrodynamic Optimization– What can be gained?23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 7Hydrodynamic Optimization– What can be gained?Source: WärtsiläSuH 201023.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 8Hydrodynamic Optimization– What can be gained?Ship Design ShipHull / Propulsor Operation- Main dimensions- Ship lines- detailed geometries - Optimium trim- Propulsor design point - Off Design conditions- Appendages - Added resistance- Optimize hull surface - Fleet speed optimisation- Energy saving devices - Operating profile- Renewable energies- Air cushion system23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 9Hydrodynamic Optimization– What can be gained?Source: MAN 201023.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 10Optimal Main Dimensions and Hull FormBased on the example of a13000 DWT Product Tanker23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 11Optimal Main Dimensions and Hull FormInfluence on Power DemandNew building, delivered 1994 Project (restricted Dimensions)Length between pp 135,70 m Length between pp 118,50 mBreadth moulded 19,60 m Breadth moulded 21,50 mDepth to main deck 10,65 m Depth to main deck 11,00 mDraught scantling 8,40 m Draught scantling 8,50 mDeadweight all told 13000 dwt Deadweight all told 13000 dwtCargo tank volume 13600 m3 Cargo tank volume 13600 m3Speed at same Pd 14,9 kn Speed at same Pd 14,1 kn25 % at 14.5 kn !Power at SS4, BF5 3300 kW Power at SS4, BF5 3300 kW+Service speed 14,5 kn Service speed 14,5 knPower at SS4, BF5 3000 kW Power at SS4, BF5 3750 kW23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 12Optimal Main Dimensions and Hull FormExample: RoRo-VesselThe Designer defined too strict hardpoints concerning arrangement ofgear box and main engineThe resulting hullform (black lines)showed an unexpected high powerdemand in propulsion testSmoothen the aft shoulder waspossible by lifting up gear box, mainengine and main deck!Gain by smoothen the aft shoulder (redlines) : 17% at design speed23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 13Optimal Main Dimensions and Hull FormExample: Ice Class TankerThe designer tried to reducefabrication costs by applying a toosmall bilge radius (black lines)CFD calculations (potential flow) cannot predict separationsIn the paint flow tests separations inthe bilge area became visibleGain by rounding the bilge area in thefore body (red lines) : 8-10%23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 14Ship / Fleet OperationShips in OperationSlow SteamingNew Paints, Better Fabrication, Air LubricationOperational ProfileEnergy saving devicesRenewable Energies23.11.2010 FRIESCH Hydrodynamic Optimizsation of Ships BSPC 2010 15Slow Steaming23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 16Slow Steaming23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 17EEDISource: MEPC 6023.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 18EEDISource: Krapp GL 200923.11.2010 FRIESCH Hydrodynamic Optimzation of Ships BSPC 2010 19EEDI23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 20Minimizing Hull Resistance23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 21Minimizing Hull ResistanceΔV ≈ -0.2 knSΔV ≈ +0.3 knSSpeed23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 22rewoPMinimizing Hull ResistanceThe quality of the type of paint (anti-fouling) may influence the fuel oil consumptionsignificantly, application of air cushions is also a possibility2600AHR = 200 μmAHR = 150 μm2400 AHR = 100 μm2200+1.7% RT2000⇒ -0.1kts1800-2.0% RT⇒ +0.1kts1600140022.5 23.0 23.5 24.0 24.5 25.0 25.5 26.0 26.5Ship Speed [kts]23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 23]Nk[ecnatsiseRpihSMinimizing Hull Resistance23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 24Minimizing Hull Resistance23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 25Minimizing Hull ResistanceImperfect Surfacesby bumps and welding seams23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 26Minimizing Hull ResistanceTests with different bodies:Full optimised shape,with bumps, with welding seams, with bumps and welding seams23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 27Minimizing Hull ResistanceSpeed m/s23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 28NecnatsiseRMinimizing Hull Resistance4. Improve the hull surface by using improved, less rough paints5. Polish welding seams6. Avoid bumps and large deformations of the shell plates23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 29How to operate a ship hydrodynamical efficient !The reduction inrequired powerbetweenthese two forms isabout 16% !Look forOff-designconditionsWave pattern atreduced draughtand reduced speed23.11.2010 FRIESCH Hydrodynamic Optimizsation of Ships BSPC 2010 30How to operate a ship hydrodynamical efficient !Look forOptimum TrimconditionsGain up to 7%,but also if done wronglosses up to 5% possible23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 31Optimise the Arrangement of Hull, Rudder, PropellerHull designer, rudder designerand propeller designer have towork in close co-operationApplying a ducktail (with trimwedge) may gain up to 2-3%Optimum rudder and propellerposition may gain up to 1-2%Applying a rudder bulb maygain additionally 1-2%5% in Power are equal to a gain in speed of 0.26 knots for this Project23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 32Devices improving Propulsive Efficiency23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 33Devices improving Propulsive Efficiency23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 34Devices Improving Propulsive EfficiencyPre Swirl Fin Systems Designer DSME gain up to 4%Rudder Fin Systems Designer HHI gain up to 4%Twisted Rudder with Costa Bulb Designer BMS/HSVA gain up to 4%Mewis Duct Designer BMS / Mewis gain up to 8%Pre Swirl Fins Rudder Fins Twisted Rudderwith Costa BulbHHI BMS/HSVADSME23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 35High Efficiency Propellers~ 5 %3-5 %8-10 %3-bladed Propeller for VLCCKappel-PropellerContra-rotating Propellers23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 36High Efficiency PropellersSource: MMG 201023.11.2010 FRIESCH Hydrodynamic Optimizsation of Ships BSPC 2010 37Alternative Ways to GoAlternative Ways8800%%LNG7700%%ssmmee6600%% yy ss ttNuclear Powe eer llll SSCCee ll5500%% FF uu CCoommbbiinneedd GGaass--//Current SStteeaamm TTuurrbbiinneeStatus4400%%Renewable EnergiesSShhiipp EEnnggiinneess3300%%SStteeaamm TTuurrbbiinneeGGaass TTuurrbbiinnee2200%%Fuel Cells110000 11 000000 1100 000000 110000 000000 11 000000 000000EElleeccttrriicc PPoowweerr [[kkWW]]23.11.2010 FRIESCH Hydrodynamic Optimizsation of Ships BSPC 2010 38yyccnneeiicciiffffEEcciirrttcceellEEWind Power23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 39Wind Power23.11.2010 FRIESCH Hydrodynamic Optimzation of Ships BSPC 2010 40Hydrodynamic OptCimoinzcatliuosni–oWnshat can be gained?ConclusionsOptimising main dimensions may gain up to 25%Avoiding too strict hard points may gain up to 17%Using an experienced designer may gain up to 10%Optimising the hullform may gain up to 7%Devices improving propulsion efficiency may gain up to 8%Optimising arrangement of rudder and propeller may gain up to 3%Optimising hull surface may gain up to 10%Further improvements can be achieved by optimising the whole ship forreal off-design conditions!The gains are valid for the examples shown here. The benefits given above arenot fully cumulative!23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 41Thank you for your AttentionThe best possible way to avoid pollution from shipping ???Thank you for your Attention23.11.2010 FRIESCH Hydrodynamic Optimization of Ships BSPC 2010 42
Presentation Friesch WG IMP 4th meeting 10 11 23