OpenFOAM for marine hydrodynamics CFD - foam … · resources, CFD for marine hydrodynamics is...
1
FSB University of Zagreb Fakulty of Mechanical Engineering and Naval Architecture Department of Energy, Power Engineering and Environment OpenFOAM for marine hydrodynamics CFD Vuko VUK ˇ CEVI ´ C Inno GATIN ABSTRACT This poster presents the capabili- ties of the OpenFOAM’s Naval Hy- dro pack for marine hydrodynamics CFD simulations developed within Prof. Jasak’s CFD group. The CFD model is used for accurate simulations regarding: Steady resistance with dynamic sinkage and trim, Seakeeping in head and oblique, regular and irregular sea states, Self propulsion with modelled and discretised propellers, Manoeuvring: – Turning circle, – Zig–zag tests, – Crabbing. Versatile, robust and efficient simu- lations are enabled with: Ghost–Fluid–Method: accurate treatment of discontinuities at the free surface, Interface capturing: Volume–of– Fluid or Level Set Method, Solution decomposition: calculat- ing perturbation around potential flow solution, Domain decomposition: prevent- ing wave reflection, Semi–monolithic approach: im- plicitly coupled pressure equation and rigid body equations. Steady resistance simulations Rapid steady resistance simulations are routinely performed to aid the design of ships in order to minimize fuel consumption. Image presents wave elevation for three different bow shapes, where the results have been obtained within twelve hours, including meshing, case set–up, simulations and post processing. Seakeeping simulations Fully non–linear CFD seakeeping simu- lations are becoming increasingly utilised because of their ability to accurately cal- culate added resistance of ship in waves. Reliable estimate of transfer function can be obtained within few days using a modest HPC workstation (64 CPUs). 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Dimensionless wave length, λ/L PP 0 5 10 15 20 25 30 Total resistance coefficient, C T · 10 3 Mean, navalFoam Mean, swenseFoam Mean, EXP First order, navalFoam First order, swenseFoam First order, EXP C1 C2 C3 C4 C5 Oblique wave simulations with roll motion and forward speed do not represent a diffi- culty as opposed to potential flow methods. Full scale self–propulsion One of the main benefits of CFD is its ability to calculate full scale flows without the need for error prone extrapolation of results. The Naval Hydro pack has been recently used to calculate the self–propulsion point for a 138 meters long general cargo carrier with constant propeller revolution rate. 0 100 200 300 400 500 600 700 800 Time, s 11.8 12 12.2 12.4 12.6 12.8 13 13.2 13.4 13.6 13.8 14 Forward speed, kn navalFoam, 7M mesh navalFoam, 11M mesh Sea trial, measured speed on 1st run Sea trial, measured speed on 2nd run ISO 15016 speed Reference for sea trial measurements and results: Dmitriy Ponkratov, Lloyd’s Register: Workshop on Ship Scale Hydrodynamic Computer Simulation, November 2016 Manoeuvring: turning circle Actuator disk model allows fast CFD simu- lations of different manoeuvres. Using the actuator disk model and deflected rudder, tactical diameter of the KVLCC model has been calculated. Conclusion With increasing availability of computational resources, CFD for marine hydrodynamics is gaining in popularity and slowly replacing traditional methods: experiments and poten- tial flow based numerical methods. Acknowledgements We are grateful for our industrial sponsors: Hyundai Heavy Industries and Bureau Ver- itas for supporting the development of the Naval Hydro pack. 8th Floor CFD@FSB Zagreb, 2017 Supervisor: Prof. Hrvoje Jasak www.fsb.hr/cfd Feel free to contact us at [email protected] and [email protected], or take a look at our YouTube channel: 8th Floor CFD@FSB.
-
Upload
truongliem -
Category
Documents
-
view
315 -
download
9
Transcript of OpenFOAM for marine hydrodynamics CFD - foam … · resources, CFD for marine hydrodynamics is...
9
Priručnik grafičkih standarda za oblikovanje vizualnih identiteta sastavnica
Sveučilište u ZagrebuVizualni identitet
Znak SveučilištaVerzija 2c/b pozitiv
2.2.
Crno – bijeli pozitiv znaka Sveučilišta u Zagrebu (verzija 2) standardno je reproduciran u crnoj boji Pantone Black, odnosno njenom cmyk ekvivalentu. Detaljne specifikacije nalaze se u poglavlju Program boja Priručnika grafičkih standarda za oblikovanje vizualnih identiteta sastavnica.
Radi kvalitete i preciznosti reprodukcije, znak Sveučilišta nije dozvoljeno rekonstruirati (precrtavati, skenirati...) Vektorizirani znak nalazi se na elektroničkom mediju koji je sastavni dio Priručnika grafičkih standarda za oblikovanje vizualnih identiteta sastavnica.
korekcija znaka za smanjenje od 14 mm
FSBUniversity of Zagreb
Fakulty of Mechanical Engineering and Naval ArchitectureDepartment of Energy, Power Engineering and Environment
OpenFOAM for marine hydrodynamics CFD
Vuko VUKCEVICInno GATIN
ABSTRACTThis poster presents the capabili-ties of the OpenFOAM’s Naval Hy-dro pack for marine hydrodynamicsCFD simulations developed withinProf. Jasak’s CFD group.
The CFD model is used for accuratesimulations regarding:
Steady resistance with dynamicsinkage and trim,Seakeeping in head and oblique,regular and irregular sea states,Self propulsion with modelled anddiscretised propellers,Manoeuvring:– Turning circle,– Zig–zag tests,– Crabbing.
Versatile, robust and efficient simu-lations are enabled with:
Ghost–Fluid–Method: accuratetreatment of discontinuities at thefree surface,Interface capturing: Volume–of–Fluid or Level Set Method,Solution decomposition: calculat-ing perturbation around potentialflow solution,Domain decomposition: prevent-ing wave reflection,Semi–monolithic approach: im-plicitly coupled pressure equationand rigid body equations.
Steady resistance simulations
Rapid steady resistance simulations areroutinely performed to aid the design ofships in order to minimize fuel consumption.Image presents wave elevation for threedifferent bow shapes, where the resultshave been obtained within twelve hours,including meshing, case set–up, simulationsand post processing.
Seakeeping simulations
Fully non–linear CFD seakeeping simu-lations are becoming increasingly utilisedbecause of their ability to accurately cal-culate added resistance of ship in waves.Reliable estimate of transfer function canbe obtained within few days using a modestHPC workstation (64 CPUs).
0.6 0.8 1 1.2 1.4 1.6 1.8 2Dimensionless wave length, λ/L
PP
0
5
10
15
20
25
30
Tota
l re
sist
ance
coef
fici
ent,
CT · 1
03
Mean, navalFoam
Mean, swenseFoam
Mean, EXP
First order, navalFoam
First order, swenseFoam
First order, EXP
C1 C2 C3 C4 C5
Oblique wave simulations with roll motionand forward speed do not represent a diffi-culty as opposed to potential flow methods.
Full scale self–propulsion
One of the main benefits of CFD is its abilityto calculate full scale flows without the needfor error prone extrapolation of results. TheNaval Hydro pack has been recently usedto calculate the self–propulsion point for a138 meters long general cargo carrier withconstant propeller revolution rate.
0 100 200 300 400 500 600 700 800Time, s
11.8
12
12.2
12.4
12.6
12.8
13
13.2
13.4
13.6
13.8
14
Forw
ard s
pee
d, kn
navalFoam, 7M mesh
navalFoam, 11M mesh
Sea trial, measured speed on 1st run
Sea trial, measured speed on 2nd run
ISO 15016 speed
Reference for sea trial measurements and results:Dmitriy Ponkratov, Lloyd’s Register: Workshop on Ship Scale Hydrodynamic Computer Simulation, November 2016
Manoeuvring: turning circle
Actuator disk model allows fast CFD simu-lations of different manoeuvres. Using theactuator disk model and deflected rudder,tactical diameter of the KVLCC model hasbeen calculated.
Conclusion
With increasing availability of computationalresources, CFD for marine hydrodynamicsis gaining in popularity and slowly replacingtraditional methods: experiments and poten-tial flow based numerical methods.
Acknowledgements
We are grateful for our industrial sponsors:Hyundai Heavy Industries and Bureau Ver-itas for supporting the development of theNaval Hydro pack.
8th Floor CFD@FSB
Zagreb, 2017Supervisor: Prof. Hrvoje Jasak
www.fsb.hr/cfdFeel free to contact us at [email protected] and [email protected], or take a look at our YouTube channel: 8th Floor CFD@FSB.
