电子器件 技术文件StructuralMechanics1_Minicourse_2015.pptxVIP

StructuralMechanicsI:

StaticsandDynamicsHenrikS?nnerlind

AgendaStructuralmechanicsphysicsinterfaces

-Overview

-Howtoselect

-Properties

-MixingdifferentelementtypesStudytypesContactanalysisModellingtechniquesMultibodydynamics

ProductSuite–COMSOL?5.2Productswithstructuralmechanicsfunctionality

SolidMechanicsThemostgeneralapproachtostructuralmechanics

-3D(u,v,w)

-2Daxisymmetry(u,w)

-2Dplanestress(u,v,wZ)orplanestrain(u,v)

MaterialModelsStructuralMechanicsModuleLinearElasticViscoelasticPiezoelectricExternalStress-StrainRelationNonlinearStructuralMaterialsModuleHyperelasticNonlinearElasticPlasticityCreepViscoplasticityGeomechanicsModuleNonlinearElasticPlasticitySoilPlasticityCam-ClayCreepConcreteRocks

ShellandPlateForthinstructures

-3D(u,v,w,arx,ary,arz)

-Definedbymid-surfacegeometry.Use’offset’tore-position.

-Input:Material(linearelastic),thickness

-Assumption:NostressinnormaldirectionThePlateinterfaceisa2DspecializationoftheShellinterface

Shell–rotationaldegreesoffreedomTherotationaldegreesoffreedomarethe“shellnormaldisplacements”.Nna|N|=|n|=1

Shell–LocalcoordinatesystemThelocalsystemisintheplaneoftheshellProjectionoftheassignedsystem

Shell-resultsManyresults,suchasstresses,varythroughthethickness

-ModifyevaluationpositionduringpostprocessingIntegratedquantites(sectionforcesandmoments)Worstoftopandbottom(e.g.shell.mises_max)1=Top0=Mid-surface-1=Bottom

MembraneForthinstructures(thinnerthanashell)

-3D(u,v,w,unn)

-2Daxisymmetry(u,w,unn)NegligiblebendingstiffnessAlmostalwaysgeometricallynonlinearNeedstensileprestresstobestableMaterialmodels:LinearElastic,

NonlinearElastic,Hyperelastic,Plasticity,Viscoelasticity,CreepInput:Material,thickness

BeamBeamsareslenderstructureswhichcancarryaxialforces,shearforces,bendingmomentsandtwistingmoments

-3D(u,