1Example32TitleEigenvalueanalysisofasimplysupportedshaftDescriptionCalculatethenaturalfrequenciesofasimplysupportedshaft.StructuralgeometryandanalysismodelVerificationExample2MODELAnalysisType2-Deigenvalueanalysis(X-Yplane)UnitSystemin,lbfDimensionLengthL=100inWeightdensityγ=7.764×10-4lbf⋅sec2/in4Gravitationalaccelerationg=1.0in/sec2ElementBeamelementMaterialModulusofelasticityE=30×106psiSectionPropertyAreaA=0.31416in2MomentofinertiaIyy=0.15708in4RadiusR=1.00inThicknesst=0.05inBoundaryConditionNodes1and21;ConstrainDxandDz.AnalysisCaseSelfweightisconvertedtonodalmassesautomatically.Numberofnaturalfrequenciestobecomputed=6Example323ResultsEigenvalueAnalysisResultsEigenvalueAnalysisResultsVerificationExample4ComparisonofResultsUnit:HzNaturalfrequencyRef.1MSC/NASTRANMIDAS/Genf121.833521.833521.8335f287.333987.333387.3333f3196.501196.494196.494f4349.335349.294349.294f5545.837545.670545.670f6786.005785.476785.476ReferencesJ.P.DenHartog,“MechanicalVibrations”,4thEdition,McGraw-Hill,NewYork,1956,p.432.“MSC/NASTRAN,VerificationProblemManual”,V.64,TheMacNeal-SchwendlerCorporation,1986,ProblemNo.V0306.
