AIAA 4th Drag Predicon Workshop...AIAA 4th Drag Predicon Workshop June 20‐21, 2009, San Antonio, TX 1 U. Goldberg, O. Peroomian, V. Akdag, V. Gupta,

AIAA4thDragPredic0onWorkshopJune20‐21,2009,SanAntonio,TX

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U.Goldberg,O.Peroomian,V.Akdag,V.Gupta,S.ChakravarthyMetacompTechnologies,Inc.,

andR.Ranjan,A.Singh,A.Khare,K.Nikam

Computa0onalResearchLaboratories,Ltd.,Pune,India

AIAA4thDragPredic0onWorkshop

CORRESPONDINGPARTICIPANT’SINFORMATION

Name:Dr.UrielGoldbergEmail:[email protected]:(818)735‐4880ext.225Address:MetacompTechnologies,Inc.Address:28632BRoadsideDrive#255Address:AgouraHillsAddress:CA91301‐6071

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AIAA4thDragPredic0onWorkshop

Contents•  Solverinforma0on

•  Computedcases

•  Gridinforma0on

•  Solu0onplaMorms

•  Sampleofresults

•  Summary

AIAA4thDragPredic0onWorkshop

SOLVERINFORMATION

•  METHODNAME:CFD++So`wareSuite.•  BASICALGORITHM:finitevolumeunstructured

mixed‐elementcell‐based.•  TURBULENCEMODELS:(1)wall‐distance‐freerealizablek‐ε

(incl.eme‐scalerealizability),(2)S‐A.•  Tu=2.0%,μt/μ=3.0.•  RESIDUALS:Basedonabsolutevaluesumoverallcells,

dividedbythenumberofcells.Residualsareavailableforallequaeonsseparately.

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AIAA4thDragPredic0onWorkshopTESTCASES(NASACRMconfiguraeon,freeair,fullyturbulent)

(1.1)GridconvergencestudyatM=0.85,CL=0.500±0.001•  Tailincidenceangle=0•  Coarse,medium,fine,extra‐finegrids•  Rec=5×106basedoncREF=275.80”•  TREF=100°F(1.2)DownwashstudyatM=0.85•  UseMediumgrid•  Dragpolarsatα=0.0,1.0,1.5,2.0,2.5,3.0and4.0°•  Tailincidenceangles:‐2.0,0.0and+2.0°•  Notail•  Trimmeddragpolarderivedfrompolarsat‐2.0,0.0and+2.0°•  Δdragpolaroftailonvs.tailoff•  Rec=5×106basedoncREF=275.80”•  TREF=100°F•  Momentref.center:XREF=1325.90”,ZREF=177.95”(2.0)Machsweep:M=0.70,0.75,0.80,0.83,0.85,0.86,0.87•  Mediumgrid•  WBHiH=0•  Cl=0.400,0.450,0.500

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AIAA4thDragPredic0onWorkshopGridsizes(1/2model)

Gridinforma0on

•  GRID‐GENERATORNAME:MIME(Mule‐purposeIntelligentMeshingEnvironment).

•  GRIDTYPE:Mixedelements.Prismlayersaregrownfromallsurfacesoftheaircra`,transieoningtotetrahedralelementswithinthevolume.Inthetransieonzonebothhexahedralandpyramidelementscanappear.

•  BL1stcellsize:5.08X10‐5m(y+<1)•  BLmax.growthrate:1.235

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Config. Coarsest Coarse Medium Fine ExtraFine

WB 17.0M

WBH 11.5M 16.6M 22.7M 28.6M 33.9M

AIAA4thDragPredic0onWorkshopSOLUTIONINFORMATION

Twocompuengplarormswereused:(1)forpreliminarycalculaeonsandCL‐driver‐basedgridsensievityassessment(Task1.1)and(2)forpreparaeonofpolarsandMachsweepdata(Tasks1.2&2.0).

Plarorm1

•  COMPUTERPLATFORM:clusterofLinux‐basedmachines.Eachmachinehas2dual‐coreAMDOpteronprocessors.

•  INTERCONNECTION:infiniband‐based.•  NO.OFPROCESSORS:8machines(32CPUs).•  OPERATINGSYSTEM:Kernel2.6.9(SMP)ofLinuxfromRedHat.•  COMPILER:GNUC‐compiler.•  RUNTIMEWALL‐CLOCK:about8hoursfor400iteraeons(22.7Mcells).•  MEMORYREQUIREMENTS:79GB(22.7Mcells)

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AIAA4thDragPredic0onWorkshopPlarorm2

•  COMPUTERPLATFORM:Clusterof1800computenodes,eachcontainingdualIntelXeonquadCoreE5365,3.0GHzprocessors,.16GBmemoryand72GBHarddisk.

•  INTERCONNECTION:4XDDRInfiniband,Bandwidthof20Gbpsbidireceonal.

•  NO.OFPROCESSORS:14400Cores(7200CPUs).•  OPERATINGSYSTEM:XC‐3.2.1withlatestupdates•  COMPILER:GNUC‐compiler.•  EKADetails:Thesystemhasapeakcomputecapacityof

180teraflopsandhasachievedsustainedcomputecapacityof132.8teraflopsfortheLINPACKbenchmark.

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AIAA4thDragPredic0onWorkshop•  Sampleresults(1)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(2)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(3)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(4)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(5)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(6)

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Wing:suceonside,finemesh

AIAA4thDragPredic0onWorkshop•  Sampleresults(7)

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Wing:suceonside,finemeshTail:suceonside,finemesh

AIAA4thDragPredic0onWorkshop•  Sampleresults(8)

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Wing/fuselageseparaeonbubble

AIAA4thDragPredic0onWorkshop•  Sampleresults(9):TypicalWBHforcesconvergence

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AIAA4thDragPredic0onWorkshop•  Sampleresults(10):Cpprofiles(S‐A&k‐ε)

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Y=5my=10.874m

η=0.397

AIAA4thDragPredic0onWorkshop•  Sampleresults(11):Cpprofiles(S‐A&k‐ε)

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Y=25m

AIAA4thDragPredic0onWorkshop•  Sampleresults(12):Gridconvergencestudy(1.1)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(13):Gridconvergencestudy(1.1)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(14):Polarplots(1.2)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(15):Polarplots(1.2)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(16):Polarplots(1.2)

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AIAA4thDragPredic0onWorkshop•  Sampleresults(17):Machsweep(2.0)

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AIAA4thDragPredic0onWorkshopSummary

•  MIMEusedtogenerate5hierarchicalgrids

•  CFD++usedtocomputeCases1.1,1.2,2.0•  Mostsolu0onsgeneratedbyCRLIndia•  ResultspresentedwithS‐Aandk‐εmodels:

o  Gridconvergencesameexceptforcoarsestmesho  Wing/fuselage&wingTEsepara0onspredictedbyboth

modelsonallgrids

o  Trimmedpolarsbythe2modelsareverycloseo  Atα>3o(CDi)k‐ε>(CDi)S‐A