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Transcript of Optimalo
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AAiT,MechanicalEngineeringDepartment
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CourseObjectiveThecourseintroduces:
y Understandingofprinciplesandpossibilities ofoptimizationinEngineeringandinparticularindesigny Understandhowtoformulateanoptimumdesignproblembyidentifyingcriticalelementsy knowledgeofoptimizationalgorithms,abilitytochooseproperalgorithmforgivenproblemy Practicalexperiencewithoptimizationalgorithmsy Practicalexperienceinapplicationofoptimizationtodesignproblems
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CourseoutlineChapter1:IntroductiontoEngineeringOptimizationofDesigny Introduction: Historicalbackground,Definitionofterms,Basicconcepts,Classificationofoptimizationsproblems,y Applications:Designoptimization,benefitsofoptimization,automateddesignoptimization,whentouseoptimization,examples
Chapter2:OptimumDesignFormulationy Designmodels,Mathematicalmodels,Definingoptimizationproblem,Multiobjective
designproblems,applicationsofoptimizationindesign
Chapter3ClassicalOptimizationtechniquesy Singlevariableoptimizationy Multivariableoptimizationwithequalityandinequalityconstraints
Chapter4:Onedimensionalunconstrainedoptimizationtechniquesy Eliminationmethods:Exhaustivesearch,Intervalhalvingmethod,FibonacciMethod,GoldenSectionmethod.
y Interpolationmethods:quadraticinterpolation,cubicinterpolationy Directrootmethods: Newton'smethod,QuasiNewtonmethod,Secantmethod
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CourseoutlineChapter5:UnconstrainedOptimizationtechniquesy Directsearchmethods: Randomsearch,GridsearchMethod,Powellmethody Indirectsearch(Descent)methods: Steepestdescent(Cauchy)method,Conjugate
gradient(FletcherReeves)method,Newtonsmethod,y UnconstrainedoptimizationusingMatlab
Chapter6:ConstrainedOptimizationtechniquesy Directsearchmethods:Randomsearch,complexsearchMethod,Quadratic
programmingy Indirectmethods:Penaltyfunctionmethod,Lagrangemultipliermethody ConstrainedoptimizationusingMatlab
Chapter7:DynamicProgrammingy Introduction,Multistagedecisionprocesses,Applicationsofdynamicprogramming.
Chapter8:GeneticAlgorithmbasedOptimizationy IntroductiontoGeneticAlgorithm,ApplicationsofGAbasedoptimizationtechniques,GAbasedOptimizationusingMatlab
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ReferenceMaterials1. S.S.Rao,EngineeringOptimization,3rd edition,WileyEastern,20092. Papalambros andWilde,PrincipleofoptimalDesign,modelingand
computation,CambridgeUniversitypress,20003. Kalyanmoy Deb,EngineeringDesignforoptimization, PHI,20054. FredvanKeulen andMatthiis Langelaar,LecturenotesinEngineering
Optimization,TechnicalUniversityofDelft5. Ravindran,Ragsdell andRekalaitis,EngineeringOptimizationMethodsand
application,2nd edition,Willey,20066. Arora,IntroductiontoOptimumdesign,2nd edition,ElsevierAcademicPress,
20047. Forst andHoffmann,Optimizationtheoryandpractice,Springer,20108. Haftka andGurdal,ElementsofStructuralOptimization,3rd edition,Kluwer
academic,19919. Belegundu andChandrupatla,Optimizationconceptsandapplicationsin
Engineering,2nd edition,CambridgeUniversitypress,201110. Kalyanmoy Deb,MultiobjectiveOptimizationusingEvolutionary
Algorithms,Wiley,200211. Bendose,Sigmund,Topologyoptimizationtheoryandmethodsand
applications, Springer,2003
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PrerequisitesMathematicalandComputerbackgroundneededtounderstandthecourse:y Familiaritywithlinearalgebra(vectorandmatrixoperations)andy basiccalculusisessentialandCalculusoffunctionsofsingleandmultiplevariablesmustalsobeunderstoody FamiliaritywithMatlab andEXCELisalsoessential
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Lectureoutliney Introductiony Historicalperspectivey Whatcanbeachievedbyoptimization?y Optimizationofthedesignprocessy Basicterminology,notations,anddefinitionsy Engineeringoptimizationy Popularityandpitfallsofoptimizationy Classificationofoptimizationproblemsy Designoptimizationy Benefitsofdesignoptimizationy Automateddesignoptimizationy Examples
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IntroductionOptimizationisderivedfromtheLatinwordoptimus,thebest.Thusoptimizationfocuseson
Makingthingsbetter
Generatingmoreprofit
Determiningthebest
Domorewithless
Thedeterminationofvaluesfordesignvariables whichminimize(maximize)theobjective,whilesatisfyingallconstraints
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Introductiony Optimizationisdefinedasamathematicalprocessofobtainingthesetofconditionstoproducethemaximumortheminimumvalueofafunction
y Itisidealtoobtaintheperfectsolutiontoadesignsituation.
y Usuallyallofusmustalwaysworkwithintheconstraintsofthetime andfundsavailable,wecanonlyhopeforthebestsolutionpossible.
y Optimizationissimplyatechniquethataidsindecisionmaking butdoesnotreplacesoundjudgmentandtechnicalknowhow
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Historicalperspectivey AncientGreekphilosophers:geometricaloptimizationproblems
y Zenodorus,200B.C.:Asphereenclosesthegreatestvolumeforagivensurfacearea
y Newton,Leibniz,Bernoulli,DelHospital (1697):Brachistochrone Problem:
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Historicalperspectivey Peoplehavebeenoptimizingforever,buttherootsformoderndayoptimizationcanbetracedtotheSecondWorldWar.y AncientGreekphilosophers:geometricaloptimizationproblems
y Zenodorus,200B.C.:Asphereenclosesthegreatestvolumeforagivensurfacearea
y Newton,Leibniz,Bernoulli,DelHospital (1697):Brachistochrone Problem:y Lagrange(1750):constrainedminimizationy Cauchy(1847):steepestdescenty Dantzig (1947):Simplexmethod(LP)y Kuhn,Tucker(1951):optimalityconditionsy Karmakar (1984):interiorpointmethod(LP)y Bendsoe,Kikuchi(1988):topologyoptimization
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Historicalperspectivey Oneofthefirstproblemsposedinthecalculusofvariations.y Galileoconsideredtheproblemin1638,buthisanswerwasy incorrect.y JohannBernoulliposedtheproblemin1696toagroupofy elitemathematicians:y I,JohannBernoulli...hopetogainthegratitudeofthewholescientificcommunitybyplacingbeforethefinestmathematiciansofourtimeaproblemwhichwilltesttheirmethodsandthestrengthoftheirintellect.Ifsomeonecommunicatestomethesolutionoftheproposedproblem,Ishallpubliclydeclarehimworthyofpraise.
y Newtonsolvedtheproblemtheverynextday,butproclaimedIdonotlovetobedunned[pestered]andteasedbyforeignersaboutmathematicalthings."
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Whatcanbeachievedbyoptimization?
y Optimizationtechniquescanbeusedfor:y Gettingadesign/systemtoworky Reachingtheoptimalperformancey Makingadesign/systemreliableandrobust
y Alsoprovideinsightiny Designproblemy Underlyingphysicsy Modelweaknesses
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Whatcanbeachievedbyoptimization?Engineeringdesignistocreateartifactstoperformdesiredfunctionsundergivenconstraintsy Commongoalsforengineeringdesigny Functionalityy Betterperformance:Moreefficientoreffectivewaystoexecutetasksy Multiplefunctions:Capabilitiestoexecutetwoormoretaskssimultaneously
y Valuey Higherperceivedvalue:Morefeatureswithlesspricey Lowertotalcost:Sameorbetterownershipandsustainabilitywithlowercost
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BasicTerminology,notationsanddefinitionsRn ndimensionalEuclidean(real)spacex columnvectorofvariables,apointinRn
x=[x1,x2,..,xn]T
f(x),f objectivefunctionx* localoptimizerf(x*) optimumfunctionvaluegj(x),gj jth equalityconstraintfunctiong(x) vectorofinequalityconstrainthj(x),hj jth equalityconstraintfunctionh(h(x) vectorofequalityconstraintfunctionC1 setofcontinuousdifferentiablefunctionsC2 setofcontinuousandtwicedifferentiabledifferentiable
continuousfunctions
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Norm/Lengthofavectory Ifweletxandybetwondimensionalvectors,thentheirdot
productisdefinedas
y Thus,thedotproductisasumoftheproductofcorrespondingelementsofthevectorsxandy.
y Twovectorsaresaidtobeorthogonal(normal)iftheirdotproductiszero,i.e.,xandy areorthogonalifxy=0.
y Ifthevectorsarenotorthogonal,theanglebetweenthemcanbecalculatedfromthedefinitionofthedotproduct:
y where istheanglebetweenvectorsxandy,and||x||representsthelengthofthevectorx.Thisisalsocalledthenormofthevector
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Norm/Lengthofavectory Thelengthofavectorxisdefinedasthesquarerootofthe
sumofsquaresofthecomponents,i.e.,
y ThedoublesumofEq.(1.11)canbewritteninthematrixformasfollows
y SinceAxrepresentsavector,thetripleproductoftheaboveEq.willbealsowrittenasadotproduct:
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BasicTerminologyandnotationsDesignvariables
y Parameterswhosenumericalvaluesaretobedeterminedtoachievetheoptimumdesign.
y Theyincludesuchvaluessuchas;sizeorweight,orthenumberofteethinagear,coilsinaspring,ortubesinaheatexchanger,oretc.
y Designparametersrepresentanynumberofvariablesthemayberequiredtoquantifyorcompletelydescribeanengineeringsystem.
y Thenumberofvariablesdependsuponthetypeofdesigninvolved.Asthisnumberincreases,sodoesthecomplexityofthesolutiontothedesignproblems.
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BasicTerminologyandnotationsConstraintsy Numericalvaluesofidentifiedconditionsthatmustbesatisfiedtoachieveafeasiblesolutiontoagivenproblem.y Externalconstraintsy Uncontrolledrestrictionsorspecificationsimposedonasystembyanoutsideagency.
y Ex.:Lawsandregulationssetbygovernmentalagencies,allowablematerialsforhouseconstruction
y Internalconstraintsy Restrictionsimposedbythedesignerwithakeenunderstandingofthephysicalsystem.
y Ex.:Fundamentallawsofconservationofmass,momentum,andenergy
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Whatismathematical/EngineeringOptimization?Mathematicaloptimizationistheprocessof1. Theformulationand2. Thesolutionofaconstrainedoptimizationproblemofthe
generalmathematicalformMinimize f(x),x=[x1,x2,,xn]T subjecttoconstraints
gj(x) 0,j=1,2,,mhj(x)=0,j=1,2,.,r
Wheref(x),gj(x)andhj(x)arescalarfunctionsoftherealcolumnvectory Thecontinuouscomponentsofxiofx=[x1,x2,,xn]T arecalled
the(design)variablesy f(x) istheobjectivefunction,y gj(x) denotestherespectiveinequalityconstraints,andy hj(x)theequalityconstraintfunction
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Whatismathematical/EngineeringOptimization?y Theoptimumvectorxthatsolvestheformerlydefinedproblemisdenotedbyx*withthecorrespondingoptimumfunctionvaluef(x*).
y Ifnoconstraintsarespecified,theproblemiscalledanunconstrainedminimizationproblem
y OthernamesofMathematicalOptimizationy Mathematicalprogrammingy Numericaloptimization
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ObjectiveandConstraintfunctionsy Thevaluesofthefunctionsf(x),gj(x),hj(x)atanypointx=[x1,x2,,xn]T gj(x),mayinpractise beobtainedindifferentways
i. Fromanalyticallyknownformulae,e.g.,f(x)=x12+2x22+Sinx3
ii. Astheoutcomeofsomecomplicatedcomputationalprocesse.g.,g1(x)=a(x)amax,wherea(x)isthestress,computedbymeansofafiniteelementanalysis,atsomepointinstructure,thedesignofwhichisspecifiedbyx;or
iii. Frommeasurementtakenofaphysicalprocess,e.g.,h1(x)=T(x)To,whereT(x)isthetemperaturemeasuredatsomespecifiedpointinareactor,andxisthevectorofoperationalsettings.
PresenterPresentation NotesThe first two ways of function evaluation are by far the most common. The optimization principle that apply in these cased, where computed function values are used, may be carried over directly to also be applicable to the case where the function values are obtained through physical measurement.
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ElementsofoptimizationDesignspacey ThetotalregionordomaindefinedbythedesignvariablesintheobjectivefunctionsUsuallylimitedbyconstraintsy Theuseofconstraintsisespeciallyimportantinrestrictingtheregionwhereoptimalvaluesofthedesignvariablescanbesearched.y Unboundeddesignspacey Notlimitedbyconstraintsy Noacceptablesolutions
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Optimizationinthedesignprocess
Conventionaldesignprocess:
Collectdatatodescribethesystem
Estimateinitialdesign
Analyzethesystem
Checkperformancecriteria
Isdesignsatisfactory?
Changedesignbasedonexperience/heuristics/
wildguesses
Done
Optimizationbaseddesignprocess:
Collectdatatodescribethesystem
Estimateinitialdesign
Analyzethesystem
Checktheconstraints
Doesthedesignsatisfyconvergencecriteria?
Changethedesignusinganoptimizationmethod
Done
Identify:1. Designvariables2. Objectivefunction3. Constraints
PresenterPresentation NotesTaken from J.S. Arora Introduction to Optimum Design, fig. 1-2.
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Optimizationinthedesignprocessy Isthereoneaircraftwhichisthefastest,mostefficient,quietest,mostinexpensive?
Youcanonlymakeonethingbestatatime.
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OptimizationMethods
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ComparisonofConventionalandOptimalDesigny TheCDprocessinvolvestheuse
ofinformationgatheredfromoneormoretrialdesignstogetherwiththedesignersexperienceanintuition
y Itsadvantageisthatthedesignersexperienceandintuitioncanbeusedinmakingconceptualchangesinthesystemortomakeadditionalspecificationsintheprocedure
y TheCDprocesscanleadtouneconomicaldesignsandcaninvolvealotofcalendartime.
y TheODprocessforcesthedesignertoidentifyexplicitlyasetofdesignvariables,anobjectivefunctiontobeoptimized,andtheconstraintfunctionsforthesystem.
y Thisrigorousformulationofthedesignproblemhelpsthedesignergainabetterunderstandingoftheproblem.
y Propermathematicalformulationofthedesignproblemisakeytogoodsolutions.
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OptimizationpopularityIncreasinglypopular:y Increasingavailabilityofnumericalmodelingtechniques
y Increasingavailabilityofcheapcomputerpowery Increasedcompetition,globalmarketsy Betterandmorepowerfuloptimizationtechniquesy Increasinglyexpensiveproductionprocesses(trialanderrorapproachtooexpensive)
y Moreengineershavingoptimizationknowledge
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Optimizationpitfalls!y Properproblemformulationcritical!y ChoosingtherightalgorithmforagivenproblemyManyalgorithmscontainlotsofcontrolparametersy Optimizationtendstoexploitweaknessesinmodelsy Optimizationcanresultinverysensitivedesignsy Someproblemsaresimplytoohard/large/expensive
PresenterPresentation NotesIt is generally accepted that the proper definition and formulation of a problem takes roughly 50 percent of the total effort needed to solve it. Therefore, it is critical to follow well defined procedures for formulating design optimization problems.
The importance of properly formulating a design optimization problem must be stressedbecause the optimum solution will only be as good as the formulation.
For example, if we forget to include a critical constraint in the formulation, the optimum solution will most likelyviolate it because optimization methods tend to exploit deficiencies in design models. Also,if we have too many constraints or if they are inconsistent, there may not be a solution to thedesign problem.
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Structuraloptimizationy Structuraloptimization=optimizationtechniquesappliedtostructuresy Differentcategories:y Sizingoptimizationy Materialoptimizationy Shapeoptimizationy Topologyoptimization
t
E, R
r
L
h
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StructuraloptimizationInegrated optimaldesignofavehicleroadarm.y a)InitialFiniteElement
Model,y b)topologyoptimizedroadarm,y c)reconstructedsolidmodel,y d)FiniteElementmeshforshapedesigny e)VonMises stressoftheshapeoptimizeddesignandy f)comparisonofthe3DRoadarm beforeandaftershapedesign
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Sizingoptimizationy Inatypicalsizingproblemthegoalmaybetofindtheoptimalthicknessdistributionofalinearlyelasticplateortheoptimalmemberareasinatrussstructure.
y Theoptimalthicknessdistributionminimizes(ormaximizes)aphysicalquantitysuchasthemeancompliance(externalwork),peakstress,deflection,etc.whileequilibriumandotherconstraintsonthestateanddesignvariablesaresatisfied.
y Thedesignvariableisthethicknessoftheplateandthestatevariablemaybeitsdeflection.
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Shapeoptimizationy Shapeoptimization ispartofthefieldofoptimalcontroltheory.
y Thetypicalproblemistofindtheshapewhichisoptimalinthatitminimizesacertaincostfunctionalwhilesatisfyinggivenconstraints.
y Inmanycases,thefunctionalbeingsolveddependsonthesolutionofagivenpartialdifferentialequationdefinedonthevariabledomain.
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Shapeoptimization
YamahaR1
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Topologyoptimizationy Topologyoptimizationis,inaddition,concernedwiththenumberofconnectedcomponents/boundariesbelongingtothedomain.Suchusdeterminationoffeaturessuchasthenumberand locationandshapeofholesand theconnectivityofthedomain.
y Suchmethodsareneededsincetypicallyshapeoptimizationmethodsworkinasubsetofallowableshapeswhichhavefixedtopologicalproperties,suchashavingafixednumberofholesinthem.
y Topologicaloptimizationtechniquescanthenhelpworkaroundthelimitationsofpureshapeoptimization.
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TopologyoptimizationTopologyoptimizationisamathematicalapproachthatoptimizesmateriallayoutwithinagivendesignspace,foragivensetofloadsandboundaryconditionssuchthattheresultinglayoutmeetsaprescribedsetofperformancetargets.
y Usingtopologyoptimization,engineerscanfindthebestconceptdesignthatmeetsthedesignrequirements
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Topologyoptimizationexamples
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WhyDesignOptimization?
DesignComplexity
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Classificationsy Problems:y Constrainedvs.unconstrainedy Singlelevelvs.multilevely Singleobjectivevs.multiobjectivey Deterministicvs.stochastic
y Responses:y Linearvs.nonlineary Convexvs.nonconvexy Smoothvs.nonsmooth
y Variables:y Continuousvs.discrete(integer,ordered,nonordered)
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TypicalDesignProcess
InitialDesignConcept
SpecificDesignCandidate
BuildAnalysisModel(s)
ExecutetheAnalyses
DesignRequirementsMet?
FinalDesign
Yes
No
ModifyDesign
(Intuition)
Time
Money
IntellectualCapital
HEEDS
$
HEEDS(HierarchicalEvolutionaryEngineeringDesignSystem)
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AGeneralOptimizationSolution
Automotive CivilInfrastructure
BiomedicalAerospace
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AutomatedDesignOptimization
CreateParameterizedBaselineModel
CreateHEEDSDesignModel
ExecuteHEEDSOptimization
PlanDesignStudy
BasicProcedure:
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AutomatedDesignOptimization
Identify: Objective(s)ConstraintsDesign VariablesAnalysis Methods
Note: These definitions affect subsequent steps
CreateParameterizedBaselineModel
CreateHEEDSDesignModel
ExecuteHEEDSOptimization
PlanDesignStudy
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AutomatedDesignOptimization
InputFile(s)
ExecuteSolver(s)
OutputFile(s)
ValidateModel
CreateCAD/CAEModelsforaRepresentative Design
CreateParameterizedBaselineModel
CreateHEEDSDesignModel
ExecuteHEEDSOptimization
PlanDesignStudy
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AutomatedDesignOptimization
DefineInputFilesandOutputFiles
DefineDesignVariablesandResponses
DefineObjectives,Constraints,andSearch
Method
TagVariablesinInputFilesand
ResponsesinOutputFiles
DefineBatchExecutionCommandsforSolvers
CreateParameterizedBaselineModel
CreateHEEDSDesignModel
ExecuteHEEDSOptimization
PlanDesignStudy
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AutomatedDesignOptimization
CreateParameterizedBaselineModel
CreateHEEDSDesignModel
ExecuteHEEDSOptimization
PlanDesignStudy ModifyVariablesinInputFile
ExecuteSolverinBatchMode
ExtractResultsfromOutputFile
Optimized Design(s)
Yes
NewDesign(HEEDS)
NoConverged?
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CAEPortals
When
What
Where
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TangibleBenefits*Crashrails: 100%increaseinenergyabsorbed
20%reductioninmass
Compositewing: 80%increaseinbucklingload15%increaseinstiffness
Bumper: 20%reductioninmasswithequivalentperformance
Coronarystent: 50%reductioninstrain
*Percentagesrelativetobestdesignsfoundbyexperiencedengineers
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ReturnonInvestment
ReducedDesignCosts Time,labor,prototypes,tooling Reinvestsavingsinfutureinnovationprojects
ReducedWarrantyCosts Higherqualitydesigns Greatercustomersatisfaction
IncreasedCompetitiveAdvantage Innovativedesigns Fastertomarket Savingsonmaterial,manufacturing,mass,etc.
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Suggestsmaterialplacementorlayoutbasedonloadpathefficiency
Maximizesstiffness Conceptualdesigntool UsesAbaqus StandardFEAsolver
Topology Optimization
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WhentoUseTopologyOptimization
y Early in the design cycle to find shape conceptsy To suggest regions for mass reduction Topology
optimization
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DesignofExperiments
Determinehowvariablesaffecttheresponseofaparticulardesign
Designsensitivities Buildmodelsrelatingtheresponsetothevariables
Surrogatemodels,responsesurfacemodels
B
A
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WhentoUseDesignofExperiments
Following optimization
Toidentifyparametersthatcausegreatestvariation inyourdesign
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ParameterOptimizationMinimize(ormaximize): F(x1,x2,,xn)
suchthat: Gi(x1,x2,,xn)
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ParameterOptimizationObjective:Searchtheperformancedesignlandscapetofindthehighestpeakorlowestvalleywithinthefeasiblerange
Typicallydontknowthenatureofsurfacebeforesearchbegins
Searchalgorithmchoicedependsontypeofdesignlandscape
Localsearchesmayyieldonlyincrementalimprovement
Numberofparametersmaybelarge
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SelectinganOptimizationMethod
DesignSpacedependson:
Number,typeandrangeofvariablesandresponses
Objectivesandconstraints
GradientBased Simplex Simulated
Annealing
ResponseSurface GeneticAlgorithm Evolutionary
Strategy
Etc.
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DesignOptimizationProcedureUsingANSYSy Theoptimizationmodule(OPT)isanintegralpartoftheANSYS
programthatcanbeemployedtodeterminetheoptimumdesign.
y Whileworkingtowardsanoptimumdesign,theANSYSoptimizationroutinesemploythreetypesofvariablesthatcharacterizethedesignprocess:
y designvariables,y statevariables,andy theobjectivefunction.
y ThesevariablesarerepresentedbyscalarparametersinANSYSParametricDesignLanguage(APDL). TheuseofAPDLisanessentialstepintheoptimizationprocess.
y Theindependentvariablesinanoptimizationanalysisarethedesignvariables.
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DesignOptimizationProcedureUsingANSYSOrganizeANSYSprocedureintotwofiles:y Optimizationfiledescribesoptimizationvariables,andtriggertheoptimizationruns.y Analysisfileconstructs,analyses,andpostprocessesthemodel.y TypicalCommandsinanOptimizationFile
01020304050607080910111213
/CLEAR ! Clear model database... ! Initialize design variables/INPUT, ... ! Execute analysis file once
/OPT ! Enter optimization phaseOPCLEAR ! Clear optimization databaseOPVAR, ... ! Declare design variablesOPVAR, ... ! Declare state variablesOPVAR, ... ! Declare objective functionOPTYPE, ... ! Select optimization methodOPANL, ... ! Specify analysis file nameOPEXE ! Execute optimization runOPLIST, ... ! Summarize the results... ! Further examining results
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DesignOptimizationProcedureUsingANSYS
010203040506070809101112
/PREP7... ! Build the model using the
! parameterized design variablesFINISH
/SOLUTION... ! Apply loads and solveFINISH
/POST1 ! or /POST26*GET, ... ! Retrieve values for state variables*GET, ... ! Retrieve value for objective
function... FINISH
TypicalCommandsinanAnalysisFile
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DesignOptimizationProcedureUsingANSYSANSYSOptimizationAlgorithmsTwobuiltinalgorithmsinANSYS:y Firstordermethody Subproblemapproximationmethod(Zeroordermethod)
OtherOptimizationToolsProvidedbyANSYSy SingleIterationDesignTooly RandomDesignTooly GradientTooly SweepTooly FactorialTool
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Summary
y Designvariables:variableswithwhichthedesignproblemisparameterized:y Objective:quantitythatistobeminimized(maximized)Usuallydenotedby:(costfunction)y Constraint:conditionthathastobesatisfiedy Inequalityconstraint:y Equalityconstraint:
( ) 0g x( ) 0h =x
( )f x
( )1 2, , , nx x x=x K
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Summaryy Generalformofoptimizationproblem:
( )xxxxxhxg
xx
=
nX
f
0)(0)(
)(
:to subject
min
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Summaryy Optimizationproblemsaretypicallysolvedusinganiterativealgorithm:
Model
Optimizer
Designvariables
Constants Responses
Derivativesofresponses(designsensitivities)
hgf ,,
iii xh
xg
xf
,,
x
Engineering Optimization Course Objective Course outlineCourse outlineReference MaterialsPrerequisites Lecture outline IntroductionIntroductionHistorical perspectiveHistorical perspectiveHistorical perspectiveWhat can be achieved by optimization ?What can be achieved by optimization ?Basic Terminology, notations and definitionsNorm/Length of a vectorNorm/Length of a vectorBasic Terminology and notations Basic Terminology and notations What is mathematical/Engineering Optimization ? What is mathematical/Engineering Optimization ? Objective and Constraint functions Elements of optimizationOptimization in the design processOptimization in the design processOptimization MethodsComparison of Conventional and Optimal DesignOptimization popularityOptimization pitfalls!Structural optimizationStructural optimizationSizing optimizationShape optimization Shape optimization Topology optimizationTopology optimizationTopology optimization examplesWhy Design Optimization ?Classifications Typical Design ProcessA General Optimization SolutionAutomated Design OptimizationAutomated Design OptimizationAutomated Design OptimizationAutomated Design OptimizationAutomated Design OptimizationCAE PortalsTangible Benefits*Return on InvestmentSlide Number 50When to Use Topology OptimizationDesign of ExperimentsWhen to Use Design of ExperimentsParameter OptimizationParameter OptimizationSelecting an Optimization MethodDesign Optimization Procedure Using ANSYSDesign Optimization Procedure Using ANSYSDesign Optimization Procedure Using ANSYSDesign Optimization Procedure Using ANSYS Summary Summary Summary