压力容器内液体沸腾爆炸之破损研究

NationalKaohsiungFirstUniversityofScienceandTechnologyStudyofthedamagemechanismduetoboilingliquidexplosioninsideapressurevesselWen-RuiAluChen-HuaWangAThesisSubmittedtoDepartmentofSafety,HealthandEnvironmentalEngineeringNationalKaohsiungFirstUniversityofScienceandTechnologyInPartialfulfillmentoftheRequirementsFortheDegreeofMasterInSafety,HealthandEnvironmentalEngineeringJuly2003Yenchao,Kaohsiung,Taiwan,RepublicofChina-i-(BLEVE)BLEVE-ii-StudyofthedamagemechanismduetoboilingliquidexplosioninsideapressurevesselAbstractDuringthedesignlife,thesafetyaswellasreliabilitycanbegreatlydegradedduetoaging,corrosion,andwearcausedbystressesinducedintheextremeworkingconditionenduredbytheequipmentinaprocessplant.Bolingliquidexpandingvaporexplosion(BLEVE)isanextremelycomplicatedphenomenonanddamagecausedbyBLEVEisclosetocatastrophic.Inthepast,studiesofBLEVEareextremelybiased.Ononehand,thestructuralconditionisunaccountedforinordertoinvestigatethoroughlythechemical/physicalmechanismsinsidethepressurevessel.And,ontheotherhand,studiesofcrackgrowthandfragmentationofthevesseloftenassumeaconstantinternalpressure.However,itisofutmostimportancetoapprehendthewholeBLEVEprocessifonewishestopredictandpreparefortheworst.Inthisresearch,wemanagedtocollectasmanymaterialstoaccountforthewholeBLEVEprocess:initialleakduetostructurecrack,internalflashingoccurred,crackgrowthpickingupwhilethepressurecontinuingtoincreaseatanenormousspeed,andthenexplosionoccursItisnotinourintenttoquantifyBLEVE,insteadthemaingoalistoachieveacomprehensiveunderstandingofhoweachofthekeyparameterschangesduring-iii-BLEVE.Withtheknowledgelearnedinthestudy,wewishtoprovideplantpersonnelapracticalguidanceonwhetherornotfragmentationwouldoccurduringBLEVE.Keyword:Pressurevessel,Boilingliquid,crack,fragment,damage-iv-…-v-()-vi-.....................................................................................................i...............................................................!...........................................................................................................iv.........................................................................................................v.......................................................................................................vi.......................................................................................................ix.........................................................................................................x...............................................................................................11-1....................................................................................................................11-2........................................................................................21-2-1BLEVE....................................................................................21-2-2BLEVE....................................................................................31-2-3.............................................................................................41-2-4.............................................................................................51-2-5...........................................................................141-2-6...........................................................................................171-2-7...............................................................................171-3..............................................................................................191-4...........................................................................................................20BLEVE................................................212-1BLEVE.............................................................212-1-1BLEVE..............................................................................242-1-2...............................................................................252-1-3t∆..................................................................................262-2BLEVE...........................................................................262-3BLEVE.......................................................30-vii-2-3-1...............................................................................312-3-2BLEVE..............................................................................342-3-3...............................................................................372-3-4...........................................................................392-4..................................................................................................................40BLEVE.............................................413-1BLEVE.........................................................................................413-1-1(leak-before-break)............................................................423-1-2...........................................................................................433-1