2018傳熱傳質(zhì)學(xué)年會(huì)集

學(xué)科類別:傳熱傳質(zhì)學(xué)術(shù)會(huì) 多孔介質(zhì)對(duì)T型方管內(nèi)直接接觸凝結(jié)王杰1白拴龍 盧濤 ：本文通過(guò)實(shí)驗(yàn)研究了多孔介質(zhì)對(duì)T型方管內(nèi)直接接觸凝結(jié)壓力振蕩的影響。研究結(jié)果表明：未：T型方管，蒸汽直接接觸凝結(jié)，多孔介質(zhì)，壓力振蕩EffectofPorousMediaonPressureOscillationof DirectContactCondensationinaRectangularT-junction BAIShuan- LU(1.SchoolofMechanicandElectronicEngineering,BeijingUniversityofChemicalTechnology,2.BeijingAerospaceMeasurement&ControlTechnology ,Beijing :EffectsofporousmediaonthedirectcontactcondensationpressureoscillationinarectangularT-pipewerestudiedexperimentally.Theresultsshowthat,theintensityofpressureoscillationdecreasesastheincreasingofthe massflowunderthesamewatertemperatureandthewatertemperatureincreases.Fillingporousmediadoesnotweakentheintensityofthecondensationpressureoscillation,buttheintensityofthecondensationpressureoscillationisrelativelystable.Fillingofporousmediamakestheamplitudedistributionrelativelydispersed.Thepeakvalueofthepressureoscillationreducedremarkably.Thepressureoscillationfrequencyhastheobvious frequencyislowwithouttheporousmedia.Thefrequencyincreaseswiththeincreaseof flowfirst,thendecreasesandthenincreases.Byfillingporousmedia,thefrequencyofcondensationpressureoscillationincreases,alargenumberofharmonicfrequenciesappearandthereisnostablesinglefrequency. directcontactcondensation;porousmedia;pressure0前蒸汽直接接觸凝結(jié)(DirectContactCondensation,SDCC)過(guò)程中由于凝結(jié)相變 ，ha[3力相結(jié)的方法研究了振區(qū)chuggg的凝結(jié)壓振蕩特獲得在不reu[]kahan[]Li等.56]han[][7又對(duì)TTu.[8]對(duì)蒸汽浸沒(méi)射流凝結(jié)引起的沖擊特性進(jìn)行了實(shí)驗(yàn)研Hog等9]1012同時(shí)分析凝結(jié)壓振蕩的一主頻第二主頻第一主是由汽尾部的蕩導(dǎo)，此外還有學(xué)者對(duì)多孔射流凝結(jié)壓力振蕩特性進(jìn)行了研究。Hong等[9]研究多種形式等[13]144個(gè)孔的多孔噴灑器，發(fā)現(xiàn)T型方管內(nèi)直接接觸凝結(jié)開(kāi)展實(shí)驗(yàn)研究，T型方管內(nèi)直接接觸凝結(jié)的壓力振T型方管內(nèi)蒸汽直接接觸凝結(jié)過(guò)程壓力振蕩特性的影響，實(shí)驗(yàn)系1為填充/T型管道內(nèi)蒸汽與過(guò)冷水直接接觸凝結(jié)實(shí)驗(yàn)溫度、壓力系統(tǒng)。飽和蒸汽由額定功率為36KW,額定最大產(chǎn)氣量為50kgh-1的為0.2~5m3h-1，精度為0.25%FS。蓄內(nèi)安裝有兩個(gè)12kW和6kW的電加熱器，外道和蓄上包裹有一層50mm厚的保溫材料。1Fig.1Schematicdiagramofexperimental(a)多孔介質(zhì)內(nèi)部排列方式 (b)測(cè)點(diǎn)位置分布圖2排列方式和測(cè)點(diǎn)位置Fig.2themeasuringpoint實(shí)驗(yàn)T型管段材料為304不銹鋼。如圖2(a)所示，T mm。填充直徑=10mm的不銹鋼球組連接，并與T型方管的內(nèi)壁面固定。CYYZ16-P-67-A1-17-B-G-D的壓力傳感器，量程為-0.1~1MPa（表壓，精度0.1%FS。系統(tǒng)的型號(hào)為SQCSCU-4壓力系統(tǒng)。實(shí)驗(yàn)中的壓力頻率為1000Hz。實(shí)驗(yàn)時(shí)，通過(guò)調(diào)節(jié)閥調(diào)節(jié)蒸汽的質(zhì)量流量和（b）1實(shí)驗(yàn)條Tab.1Experimental冷水流量

冷水溫度

蒸汽流量

蒸汽溫度

蒸汽壓力 31.0m3h-1流量流經(jīng)填充和未填充多孔介質(zhì)P2監(jiān)測(cè)點(diǎn)測(cè)得的壓力振蕩時(shí)域信號(hào)，可以明顯看到填充多孔介質(zhì)后由于管道4所示。NN1piNN1piprmsprmspipx減去對(duì)應(yīng)工況下純pwpipxpwNpavpi的平均值。Ap1AM

pi,maxpApi,maxpiM為采樣個(gè)數(shù)。采用概率密度函數(shù)(ProbabilityDensityFunction,PDF)和累積概率函數(shù)(Cumulative實(shí)驗(yàn)中將壓力振蕩原始信號(hào)利用奇異譜分析(SingularSpectrumysis,SSA)進(jìn)行快速傅里葉變換(FastFourierTransform,FFT)，即由時(shí)域信號(hào)轉(zhuǎn)化為頻域信號(hào)，從頻域信號(hào)中壓力振蕩信號(hào)、壓力振蕩的振蕩強(qiáng)度和振蕩主頻的最大不確定度分別為1.5%、0.6%、11.4%、18.3%14.6%。GG=1.0m3h-pp/50---

未填未填充多孔介填充多孔介pwpw/50- 圖3P2監(jiān)測(cè)點(diǎn)純過(guò)冷水壓力振 圖4壓力振蕩平均值隨過(guò)冷水流量的變Fig.3Pressureoscillationofsubcooledwateratpoint

Fig.4Averageofpressureoscillationvariationwithsubcooledwatermassfluxrate實(shí)驗(yàn)結(jié)50℃時(shí)，壓力振蕩均方根值的變化prmsprms/

Tf=30

TfTf=未填充多孔介 填充多孔介G=0.3m3h- G=0.5m3h- G=1.0m3h- G=1.5m3h- prmsprms/

TT=未填充多孔介 填充多孔介G=0.3m3h- G=0.3m3h-G=0.5m3h- G=0.5m3h-G=1.0m3h- G=1.0m3h-G=1.5m3h- G=1.5m3h- Tf=40prmsprms/

TT=未填充多孔介 填充多孔介G=0.3m3·h- G=0.3m3h-G=0.5m3·h- G=0.5m3h-G=1.0m3·h- G=1.0m3h-G=1.5m3·h- G=1.5m3h-prmsprms/

TT=未填充多孔介 填充多孔介 Tf=50 (d)Tf=605壓力振蕩均方根值隨蒸汽流量的變Fig.5RMSofpressureoscillationvariationwithflow質(zhì)的情況下，蒸汽流量從10kg?h-1增大到50kg?h-1的過(guò)程中，凝結(jié)流型依次經(jīng)過(guò)間歇凝概率密度函數(shù)(ProbabilityDensityFunction,PDF和累積概率函數(shù)(CumulativePDFCPF可以清晰的展現(xiàn)出壓力振蕩幅值的分布規(guī)律。6PDFCPF隨蒸汽流量的變化規(guī)律。PDFCPF的變化趨勢(shì)CPFCPF圖變得相對(duì)平PDF圖上得到的規(guī)律相同。未填充多孔介質(zhì)的情況下，PDF型處于穩(wěn)定射流狀態(tài)。填充多孔介質(zhì)之后，PDF6壓力振蕩的PDF和CPF隨蒸汽流量的變Fig.6VariationsofpressureoscillationPDFandCPFwith flow7壓力振蕩的PDF和CPFFig.7VariationsofpressureoscillationPDFandCPFwiththesubcooledwaterflowTf=30Tf=508壓力振蕩峰Fig.8thepeakofpressure67PDF變得“矮CPF變得相對(duì)平緩，這是由于隨著過(guò)冷度的降低，凝結(jié)驅(qū)動(dòng)勢(shì)降低導(dǎo)致凝結(jié)速率PDF與CPF的變化相對(duì)較小。造成這種現(xiàn)象原因仍歸因于由于多孔介質(zhì)的填充凝結(jié)流8Tf30Tf50時(shí)凝（）9Fig.9FrequencyspectrumofpressureGw=0.5m3·h-1Tf=30℃時(shí)凝結(jié)壓力振蕩主結(jié)T型管內(nèi)蒸汽直接接觸凝結(jié)壓力振蕩的研究，填充多孔介質(zhì)并未削弱凝結(jié)壓力振蕩強(qiáng)度，相反在過(guò)冷水溫度高于50℃的工況PDFCPF)YANGWZ.Heatandmasstransfermechanismandnumericalsimulationof inreservoirporousmedia[D].Daqing:DaqingPetroleumInstitute,2010.(in) LIUSQExperimentalstudyofdirectcontactcondensationinstructuredpacking[D].Tianjin:TianjinUniversity,2013.(in CHANCK,LEECB.Aregimemapfordirectcontactcondensation[J].InternationalJournalofMultiphaseFlow,1982,8(1):11-20.GIUSEPPEG,TAKAHASHIMinoru,PELLEGRINIM,MEREUR.Experimentalstudyonchuggingphenomenoninaverticalsparger[J].InternationalJournalofMultiphaseFlow,2017,88:87-LISQ,WANGP,LUT.NumericalsimulationofdirectcontactcondensationofinjectedinawaterpoolusingVOFmethodandLESturbulencemodel[J].ProgressinNuclearEnergy,2015,78:201-215.LISQ,WANGP,LUT.CFDbasedapproachformodeling –waterdirectcontactcondensationinsubcooledwaterflowinateejunction[J].ProgressinNuclearEnergy,2015,85:729-746.LISQ.Numericalandexperimentalstudyof directcontactcondensationinateejunction[D].Beijing:BeijingUniversityofChemicalTechnology,2016.(in WUX,YANJ,LIW,PAND,LIUG.Experimentalstudyona -driventurbulentjetinsubcooledwater[J].NuclearEngineeringandDesign,2010,240(10):3259-3326.HONGSJ,PARKGC,CHOS,SONGC.Condensationdynamicsofsubmerged jetinsubcooledwater[J].InternationalJournalofMultiphaseFlow,2012,39:66-77.QIUB,ZHAOQ,ZHAOW,YANJ,LIUJ.Frequency ysisandamplitudecharacteristicsofpressureoscillationfor jet[J].CIESCJournal,2014(S1):39-43.QIUB,TANGS,YANJ,LIUJ,CHONGD,WUX.Experimentalinvestigationonpressureoscillationscausedbydirectcontactcondensationofsonic jet[J].ExperimentalThermalandFluidScience,2014,52:270-277.QIUB,YANJ,LIUJ,CHONGD,ZHAOQ,WUX.Experimentalinvestigationontheseconddominantfrequencyofpressureoscillationforsonic jetinsubcooledwater[J].ExperimentalThermalandFluidScience,2014,58:131-138.PARKCK,SONGCH,JUNHG,YOUN