低雷諾數下新型強化傳熱管的研究與開發(fā).pdf

1、鄭州大學碩士學位論文低雷諾數下新型強化傳熱管的研究與開發(fā)姓名：朱青申請學位級別：碩士專業(yè)：化工過程機械指導教師：董其伍20070425AbstractHeatexchangersareuniversalequipmentsusedinmanyindustrialfieldssuchaschemicalindustrypetroleumrefiningindustrypowerindustryfoodindustrylightindust

2、ryatomicenergyinstallation，medicinemanufacturingindustryaerospaceindustryandsoOilInthethermodynamicsystemtheinvestmentofheatexchangersisinhiigherproportioninthegrossinvestmentofanenterpriseandtheperformanceofheatexchange

3、rsdirectlyinfluencesthethermalcostInrecentyears，becauseofmanyfactorssuch髂processrequirements，energycrisisete，theresearchonheattransferenhancementtechniqueshaSbeenanimportantwaytosaveenergynowadaysTheshell—and—tubeheatexc

4、hangerhasmanyadvantagessuch嬲reliablestructurematuretechniques，wideapplicationandSOon，soitisthemostfrequentlyusedstructureinthethermodynamicsystempresentlyItgetsimprovedanddevelopedcontinuouslywiththegreatprogressoftheres

5、earchmethodonheattransferenhancementtechniquesandmodemdesignTheresearchonheattransferenhancementforthetube—sideoftheshellandtubeheatexchangeriscarriedoutbytheoreticalanalysis，numericalsimulationandexperimentsinthisdisser

6、tationConcretelytheissueofheattransferaugmentationisresearchedinallusiontothewidelyexistedproblemofthelowheattransfercoefficientoflaminarconvectiveheattransferintubesAnewtypeoftubeisfirstlyintroducedunderthedirectionofth

7、eFieldSynergyPrinciple，whichcanbemanufactureddirectlybyrollingthetraditionalsmoothpipeThemanufacturingprocedureisSOsimplethatitcostslowThenewstructurecarlmarkedlyenhancethelaminarconvectiveheattransferofthetubesideWithle

8、ssadditionalincreaseofnoWresistanceandthushasanexcellentintegratedperformanceofheattransferenhancementThemulti—longitudinalvortexflowinthenewtubeisinducedbyalternatingchangeofitscrosssection，whichistheoptimalvelocityfiel

9、dforlaminarconvectiveheattransferintubesanddoesn’teasilyattenuatealongaxialdirectionThat’SwhythenewtubecallremarkablyenhanceheattransferMeanwhile，theflowresistanceisrelativelylowSothenewstructureisasensationalkindofheatt