非對(duì)稱管殼式換熱器結(jié)構(gòu)分析及改進(jìn)中的問(wèn)題研究.pdf

1、浙江大學(xué)博士學(xué)位論文非對(duì)稱管殼式換熱器結(jié)構(gòu)分析及改進(jìn)中的問(wèn)題研究姓名：劉天豐申請(qǐng)學(xué)位級(jí)別：博士專業(yè)：化工過(guò)程機(jī)械指導(dǎo)教師：童水光林興華20051001浙江大學(xué)博士學(xué)位論文AbstractInthisthesistheheatexchangerwassummarizedcurrents廿engthcalculationmethodandtheoryoftubeandshellheatexchangerwereexpounde&and吐ea

2、pphcafionofFiniteElementAnalysis(FEAlinheatexchangerdesignwasdisplayedAsfor血eheatexchangerwhosetubesweredisposedontubesheetnonaxial—symmetricallycurrentcalculationformulacannotcheckitsstrength；onlynumericalvaluemethodcan

3、calculateitsstressByusingFEAⅡ1estrdcturestressanalysisanddesignimprovementofthisheatexchangerwithirregularlyshapedtubesheetWerestudiedhere；inaddilionrelativestrengthealculationformulaswerededucedtheoreticallyThesolidtemp

4、eraturefieldFEAtheorywasintroducedOnthewhole，andtheFEAmodelaboutthisheatexchangerstructuretemperaturefieldanalysiswassetupinreasonAftercalculation，thestructuretemperature丘elddistribution∞tteraonheatexchangerWassummarized

5、alargerdifferenttemperaturebetweenstructure’spartsWasfound，anditislikelytoengenderahighertemperaturestressMeanwhilethediffere血ebetweentwesultsunderdifferentboundaryconditionwascomparedAfeWkindsofFEAmodelaboutheatexchange

6、rstractufestressanalysiswerediscussedandthemodeltosolvethisthesis’Sproblemwasputforward：tubeWassimulatedbytrusselementandotherpartsofstructureweresimulatedbysolidelement11】estructurestressfieldandtemperaturefieldFEAmodel

7、areconsistentandthismodelensurestl】everacityofcalculationreducescalculationelementandnodesize，meanwhile，accordwi山statecriteflonandmechaniCSprincipleUnder5loadcases，thestressanalysiswasmade，andthestressdistributionfea呲ong

8、lobalheatexchangerstructureandlocaltubesheet，andthepullingawayforceontubeweresummarizedMeanwhile，itisfindthats仃ucturestrengthcheckageWasnotpassed，anddirectionideaswereputforwardforthefilturestructuredesignjmprovementS廿es

9、sanalysisandstrengthcheckageontheheatexchangerstructurewitllthickenedsheUweremade，andthecalculationresultwasanalyzedandsummarizedByanalyzingstructurestressandertemperatureloadandotherfoicelhadinoperationloadcasethephenom

10、ena山atunevendistributedtemperatureloadplaysallimportantroleonstructurestressfortheheatexchangerwithirregularlyshapedtubesheetWasfoundChangingthicknessoftubesheetFEAwasmade；itisfindthatthereafeadi／陌erentruleofstressscaleo

11、nthejointhetweentuheSheetandshellundertemperature10adotherforceloadandoperationconditionloadAccordingtnanalysisresearchresultabove，basedonpreviousheatexchangerstructuredesign，theimprovementwasmadebyadopting4measures：decr

12、easingthicknessoftuhesheet，weldingribsbetweenflange(asapartoftuhesheet)andshell，andetcThereafterthestressanalysisandstrengthcheckageaboutthisflewdesignSllUCtureweremade，andthenewonemeetsalldemandonstresssafetyanditwasapp