細(xì)水霧特性及其在狹長空間降溫效果的研究

1、申請同濟大學(xué)工學(xué)博士學(xué)位論文細(xì)水霧特性及其在狹長空間降溫效果的研究培養(yǎng)單位：一級學(xué)科：二級學(xué)科：研究生：指導(dǎo)教師：機械工程學(xué)院土木工程供熱、供燃?xì)狻⑼L(fēng)及空調(diào)工程劉乃玲張旭教授二oo六年七月AbstraetABSTRACTLiquidatomizationisfillimportantissueinmanyfieldssuchasenergypoweraerospace，agriculture，chemicalandenvironmen

2、tengineeringInmanykindsofliquidspraynozzles，pressurenozzlehasbeenwidelyusedinengineeringforitsadvantagesofsimplestructure，900datomizationreaormaneelowenergyconsumptionandsoonInthecascoflongandnarrowspacewhereagreatdealof

3、heatproducingitisfeasibletousefinemistas拙assistantmeallstolowerthelemperaturePresentlytherealenotmanyresearchesollthissubjectinthiswaythisdissertationmainlystudiesonthecharacteristicsoffreemistanditscoolingeffectsinlonga

4、ndnarrowspaceasfollows：FirstmathematicandphysicalmodelofdropletevaporationisdevelopedandsolvedDropletlifetime(evaporationtime)inairisanalyzedwiththemodelBycalculatingtwoexamples，variationruleofunsteady—statetimeisobtaine

5、daswellasthevariationruleofthetemperatureanddiameterofdropletwiththeambienttemperatureThemechanismoffinemistcoolingisanalyzedbasedontheeffectivefilmtheoryTheflowratecharacteristicandtheatomizationperformanceofseveralcomm

6、onpressarenozzlesarcstudiedandmainfactorsinfluencingthenozzle’sperformanceareanalyzedTheconclusionshowsthateharaeteristiesofnozzlesinthiskindaremainlydependedonitsdimensionandoperatingparametersFlowratecorrelationsformul

7、asandexperimentalformulasofdropletdiametersofthesepressurenozzlesarefirstregressed，andtheflowratecoefficientsofthesenozzlesarederivedaccordinglyThevariationrulesofdropletdiameterswithspraypressuresofonekindofspiralnozzle

8、arestudiedandthevalueofcriticalspraypressureofthisnozzleisderivedRulesoftemperaturedistributionwithventilationvolume，inletairtemperatureheatintensityandsprayvolumeinlongandnalTowspscetitleobtainedthroughCFDsimulationandt