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《機(jī)械諧振式熱聲制冷機(jī)的研究》由會(huì)員上傳分享,免費(fèi)在線閱讀,更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫(kù)。
1、摘要與傳統(tǒng)熱機(jī)相比,熱聲熱機(jī)(包括制冷機(jī))具有環(huán)保,無(wú)或極少的運(yùn)動(dòng)部件,高可靠性,并且可以利用低品位熱源等優(yōu)點(diǎn),因而具有極大的應(yīng)用前景。但是熱聲熱機(jī)的頻率和體積問(wèn)題卻一直制約著熱聲熱機(jī)的實(shí)用化。為尋找問(wèn)題的解決方案,本論文以熱聲冰箱為應(yīng)用對(duì)象,研究具有質(zhì)量-彈簧系統(tǒng)的機(jī)械諧振式熱聲制冷機(jī),重點(diǎn)研究諧振系統(tǒng)的模態(tài)頻率及工作特性。本文首先討論了幾種具有不同諧振腔結(jié)構(gòu)的制冷機(jī),利用等效網(wǎng)絡(luò)理論對(duì)制冷機(jī)的工作特性進(jìn)行了分析,并從尺寸大小、能量耗散和頻率調(diào)節(jié)特性等方面,討論各種結(jié)構(gòu)方案的優(yōu)缺點(diǎn),最后確定本文所采用的最優(yōu)制冷機(jī)結(jié)構(gòu)方案。對(duì)所
2、研究的制冷機(jī)裝置諧振系統(tǒng),建立了集總的二維彈簧-質(zhì)量等效模型,通過(guò)模型分析,獲得了機(jī)械諧振系統(tǒng)的模態(tài)頻率關(guān)系,并通過(guò)數(shù)值模擬研究了系統(tǒng)諧振參數(shù)對(duì)模態(tài)頻率和幅頻特性的影響,討論了系統(tǒng)調(diào)頻調(diào)諧的方法。利用對(duì)熱聲制冷機(jī)諧振系統(tǒng)的分析和模擬結(jié)果,提出了冰箱用熱聲制冷機(jī)的設(shè)計(jì)參數(shù),并利用網(wǎng)絡(luò)模型對(duì)熱聲制冷機(jī)進(jìn)行了優(yōu)化設(shè)計(jì),確定了制冷機(jī)實(shí)驗(yàn)樣機(jī)的主要結(jié)構(gòu)參數(shù),為實(shí)驗(yàn)研究對(duì)制冷機(jī)進(jìn)行了性能預(yù)測(cè)。本文的最后在建立系統(tǒng)的分布參數(shù)模型、利用DeltaE計(jì)算制冷機(jī)的聲場(chǎng)分布和能量損耗的分析等方面,為后續(xù)的研究工作提供了一些可供參考的建議。關(guān)鍵詞:熱聲
3、制冷機(jī);機(jī)械諧振;模態(tài)頻率;諧振參數(shù);網(wǎng)絡(luò)模型IAbstractComparedwiththeconventionalheatengines,thermoacousticheatengines(includingrefrigerators)havesomeadvantage,suchassimplestructure,noorleastmovingparts,highreliability,potentialpossibilityofoperatingonlowenergylevelheatsource,usingenviron
4、mentallyfriendlyworkingsubstance,andetc.Forthese,thermoacousticheatenginesarebecomingsignificantlypromisinginapplications.However,thepracticalapplicationsofthermoacousticheatengineshavebeenrestrictedbysomeissuesonpowerdensityandfrequencymatching.Inordertofindthesolut
5、ionsfortheseissues,inthisthesis,amechanicalresonantthermoacousticrefrigeratorwithmass-springsystemismainlyinvestigatedfortheapplicationaimasfreezer.Thekeypointsinvestigatedareplacedonmodefrequenciesandoperatingbehaviorofresonantsystemstudied.Severalthermoacousticrefr
6、igeratorswithdifferentconfigurationsofresonatorsarefirstlydiscussedinthisthesis.Operatingbehaviorsofrefrigeratorsareanalyzedusingequivalentnetworkmethod,andthenmeritsanddrawbacksintheseaspectsofsizes,energydispersion,andcharacteristicoffrequencymodulationarecompareda
7、nddiscussedamongvariousconfigurationsofthermoacousticrefrigerators.Theoptimalconfigurationschemeisfinallydeterminedandadoptedinthisthesis.Alumpedtwo-dimensionalspring-massequivalentmodelisestablishedfortheresonantsystemofthethermoacousticrefrigeratorstudied.Thefreque
8、ncyrelationsofmodesforthemechanicalresonantsystemareobtainedanalytically.Theeffectsoftheresonantparametersforthesystemonmodefrequen