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CFD，，（，214082）：RANS。，Level－Set，Reynoldsk-ω，PISORANS。LevelSet。S60。，Level－Set。：；LevelSet；：U661.3：AOverlapgridresearchontheapplicationofshipCFDZHAOFa-ming,GAOCheng-jun,XIAQiong(ChinaShipScientificResearchCenter,Wuxi214082,China)Abstract：RANSmethodsandoverlapgridareusedtocalculatetheshipflowaroundwithfreesurface.Computationalgridisoverlapgridpattern.ThesinglephaseLevelSetmethodwasusedforthefreesurfacetreatment,theSSTk-ωturbulencemodel,cellfinitedifferencemethodandPISOalgorithmwereemployedinviscousflowcalculationwithsolvingRANSequations.ThemathematicalmodelandsolutionofoverlapgridandsimulationmethodofsinglephaseLevelSetmethodweredescribedbriefly,too.Throughthenu-mericalsolutionwithoverlapgridsandthecomparisonwithexperimentalresultsforfixandfreeS60,cata-maranandtrimaran,theoverlapgridcanwellsimulatetheviscousfree-surfaceflowaroundtheship.thecalculationresultsshowthatoverlapgridandsinglephaseLevel-Setmethodcanbettersimulatethevis-cousfree-surfaceflowaroundaship.Keywords:overlapgrid;singlephaseLevelSetmethod;viscousfree-surfaceflow1，。CFD，“”，。、，、，CFD。，，，：1007-7294（2011）04-0332-10：2010-12-05：（1979-），，。154Vol.15No.420114JournalofShipMechanicsApr.2011。（Fluent/Gambit）、，CFD，，、（、），、，CFD。（chimeragrid，oversetgrid，overlapgrid），：，，CFD。CFD，（freesurfacetracing）（freesurfacecapturing）。，，。，MAC、VOF、LevelsetVOF/Levelset。LevelSet。2，，、，。、、、，。，：NASAPEGASUS、ARLSUGGARSUGGAR++、OVERTURE，。，。1：12。1（1），2。，2（1）1，ftrilinear（1）。12。2，3。f=f1+-f1+f2!di+-f1+f4!dj+-f1+f5!dk+f1-f2-f4+f3!didj(1)+f1-f2-f5+f6!didk+f1-f4-f5+f8!djdk+-f1+f2-f3+f4+f5-f6+f7-f8!didjdk：di，dj，dk[0,1]。1Fig.1Overlapgrid4：CFD3332（x＝0.5）Fig.2Overlapgridformonohull(x＝0.5section)3Fig.3Overlapgridforshipwithappendage，，，：。（）。，，，CFD。、，。。CFD，。、334154，。，，，。，ADT，ADT。3LevelSet3.1LevelSetφ（），：坠φ坠t+ui·荦φ=0(2)：φ0=00荦荦荦荦荦φ=0（）。，φ=0：坠ui坠xi·nj=0，nj=-坠φ/坠xi坠φ/坠xi(3)p=zFr2(4)φ≤0。3.2LevelSetLevelSetLevelSet。（2）φ=0，φ，φ，z=0，。LevelSetφφ0=0（4）：φ=d（φ0=0）坠φ坠xi·nj=signφ0′′(5)φ0LevelSet。4RANS4.1Reynolds，NS，ReynoldsAveragedNavierStokes（RANS）。RANS：坠ui坠xi=0(6)坠ui坠t+uj坠ui坠xj+坠p坠xi-1Re坠2ui坠xj坠xj-坠坠xj-ui′uj′′′=0(7)，-ρui′uj′Reynolds。4Fig.4Reinitializationoffreesurface4：CFD3354.2k-ω（SST）。kω：νt=kω(8)坠k坠t+Uj-σk坠vt坠xj觶觶坠k坠xj-1Rk荦2k+sk=0坠ω坠t+Uj-σω坠vt坠xj觶觶坠ω坠xj-1Rω荦2ω+sω=0(9)，k=1.1×10-7，ω=9.0。5，：坠准坠τ=1△τ1.5准n-2准n-1+0.5准n-2觶觶(10)（7）（)，、，（7）。（2）。ADIPISO。6。，。，（11）。Ix000Iy000Iz△△△△△△△△=mrg,x2+yG2+zG2觶觶000mrg,y2+yG2+zG2觶觶000mrg,z2+yG2+zG2觶觶△△△△△△△△△△(11)，rg,jj，xG=xrot-xCG。，（12）-（13）。()，，，5，6。FCGi=md2xCGidt2LCGi=ddtIidθCGidt觶觶(12)mu觶-vr+wq-xGq2+r2觶觶+yGpq-r觶觶觶+zGpr+q觶觶觶△△=Xmv觶-wp+ur-yGr2+p2觶觶+zGqr-p觶觶觶+zGqp+r觶觶觶△△=Ymw觶-uq+vp-zGp2+q2觶觶+xGrp-q觶觶觶+yGrq+p觶觶觶△△=ZIxp觶+Iz-Iy觶觶qr+myGw觶-uq+v觶觶p-zGv觶-wp+u觶觶r△△=K(13)Iyq觶+Ix-Iz觶觶rp+mzGu觶-vr+w觶觶q-xGw觶-uq+v觶觶p△△=M336154Izr觶+Iy-Ix!pq+mxGv觶-wp+u!r-yGu觶-vr+w!q#$=N，X，Y，Z，K，M，N、、、。u，v，wx，y，z，u觶，v觶，w觶。p，q，r，p觶，q觶，r觶。5Fig.56Dofsolutionstrategy4：CFD3376Fig.6Oversetgridformotion77.1LevelSet60Fr=0.316，Re=4.3×106。：101×36×62，O74×36×59，346248，7。，y+≈0.8。△t=0.01，T=20（T1=2，19），PCCoreQuadCPU2.33G+4.0GRAM，5～10。1。（14）。z′=zLθ′=θL(14)1Tab.1DragcomparetableCPCFCTS60(fix)S60(free)CalEXPCalEXP2.012.193.513.42(ITTC57)3.563.42(ITTC57)5.525.425.755.867S60（Fr=0.316，Re=4.3×106）Fig.7Wavecontours&sinkageandtrimforS60(Fr=0.316,Re=4.3×106)3381547.2LevelSetFr=0.55，Re=1.722×106，s=0.2L。：101×56×51，O2×71×48×50，644709，8。，y+≈0.5。△t=0.01，T=10（T1=2，9），PCCoreQuadCPU2.33G+4.0GRAM，8。2[8]。9。8Fig.8OverlapgridforcatamaranCPCFCTWigley（s=0.2L）Cal[Present]Cal（[8]）EXP（[8]）5.4785.3315.4204.3054.5259.7839.8562Tab.2Dragcomparetable9（Fr=0.55，Re=1.722×106）Fig.9Wavecontoursandwaveprofileforcatamaran(Fr=0.55,Re=1.722×106)7.3LevelSetFr=0.3，Re=4.6×106。：80×45×46，O3×71×51×39，589257，10。，，y+≈0.8。4：CFD339△t=0.01，T=10（T1=2，9），PCCoreQuadCPU2.33G+4.0GRAM，8。11-13、。10，，13。10Fig.10Overlapgridfortrimaran1112Fig.11WavecontoursfortrimaranFig.12Computedtimefortrimaran8Level-Set，PISO、k-ω，RANS，，，。，Levelset13/Fig.13Waveprofilefortrimaran340154，，。Level-SetCFD，。：[1].[M].:,1992.[2]ZhangZhirong,ZhaoFeng,LiBaiqi.Numericalcalculationofviscousfree-surfaceflowaboutshiphull[J].JournalofShipMechanics,2002,6(6):10-17.[3]RogersSE.PEGASUSuser’sguide[K].~rogers/pegasus/uguide.html,Oct,2003.[4]RogersSE,SuhsNE,DietzWE.PEGASUS5:Anautomatedpreprocessorforoverset-gridcomputationalfluiddynamics[J].AIAAJournal,2003,41(6):25-51.[5]PatersonEG,WilsonRV,SternF.General-purposeparallelunsteadyransshiphydrodynamicscode:CFDSHIP-IOWA[R].IIHRTechnicalReportNo.432,2003.[6]CarricaPM,WilsonRV,NoackR,XingT,KandasamyM,ShaoJ,SakamotoN,SternF.Adynamicoversetsingle-phaselevelsetapproachforviscousshipflowsandlargeamplitudemotionsandmaneuvering[C]//Th26SymposiumonNavalHydrodynamics2006.Korea,2006.[7]ChiYang,etal.Calculationofshipsinkageandtrimusingunstructuredgrids[C]//ECCOMAS2000,11-14September2000.Barcelona,2000.[8]（）,07.ppt[J/OL].2007.4：CFD341