中文摘要低料位操作下气固挡板流化床的压力脉动特性摘要：基于当前的这一套机玻璃流化床冷模实验装置，还是应该要将CRP-1催化裂解催化剂颗粒直接幻化成为内部固体介质，并将常温空气作为一项流化介质，通过对气速的不断调节，初始装料高度（H）为450mm的操作条件下，内构件安装在静床高度上方的操作模式，分析床层内的压力脉动特性。结果表明：单构件床内平均压力随表观气速的增大将出现三个阶段：0.04≤Ug≤0.48m/s，平均压力随表观气速的增大缓慢增大；0.48≤Ug≤0.83m/s，平均压力随之快速增大；0.83≤Ug≤1.14m/s，平均压力随之几乎不变。伴随着轴向高度的不断增大，压力也会呈现出逐渐下降的情况。伴随着床层高度的逐步升高，压力脉动标准也会急剧下降。特别是在床层底端，床层升高之后，床层的中部压力脉动标准偏差随床层高度变化不大，0.6m的床层在不断增高的这一过程当中，压力脉动标准偏差比值也会呈现出先增大后减小的这一情况。当气速在0.04m/s≤Ug≤0.44m/s范围内时单构件流化床中的气固两相处于湍动流态化阶段。当0.44m/s≤Ug≤0.83m/s时，流化床内气固两相处于鼓泡-节涌过渡流态化，压力脉动功率谱密度曲线表现为单主频，并且主频密度值远大于其他频率所对应的密度值。当单构件床中气固两相处于鼓泡流态化阶段（Ug≥0.83m/s）时，主频功率与相邻频率的功率差别较鼓泡-节涌过渡流态化而言较小。关键词：气固两相流；流动特性；压力脉动；功率谱毕业设计（论文）外文摘要TitlePressurepulsationcharacteristicsofgas-solidbafflefluidizedbedunderlowleveloperationAbstractBasedonthepresentseriesofmechanicalfluidizedbedcoldmodelexperimentalapparatus,itisstillnecessarytoconvertthecrp-1catalyticcrackingcatalystdirectlyintotheinternalsolidmediumanduseambientairasafluidizingmediumforpassingthegasvelocity.Theinternalcomponentsareinstalledintheoperatingmodeabovethebedheightinordertoanalyzethepressurepulsationcharacteristicswithinthebedbycontinuouslyadjustingundertheinitialloadheight(H)450mmoperatingconditions.Theresultsshowthatthemeanpressureinthesinglecomponentlayerincreaseswithincreasingsurfacegasvelocityinthreesteps:theaveragepressureincreasesslowlywithincreasingsurfacegasvelocity;themeanpressureincreasesrapidly.Itisalmostunchanged.Astheaxialheightincreases,thepressuregraduallydecreases.Astheheightofthebedincreasesgradually,thepressurepulsationcriterionalsodecreasessharply.Inparticular,thestandarddeviationofpressurepulsationatthebottomofthebedshowsthestandarddeviationofthepressurepulsationatthecenterofthebed,whenthestandarddeviationofthepressurepulsationincreasesfirstandthendecreasesintheprocessofincreasingtheheightofthe0.6mbed,whichishardlychangedbytheheightofthebed.Whenthegasvelocityisintherangeof0.04M/sUg0.44M/s,≦≦gas-solidtwo-phaseflowinasinglecomponentfluidizedbedisatthestageofTurbulentFluidization.Inthecaseof0.44m/sUg0.83M/s,thegas-solidphasein≦≦thefluidizedbedisinbubblingbottletransitionfluidization,andthepressureripplepowerspectraldensitycurveappearsasasingledominantfrequencyandismuchlargerthanthedensityvaluecorrespondingtotheotherfrequencydensityvalue.Whengas-solidtwo-phaseinasinglecomponentbedisatbubblingfluidizationstage(Ug0.83M/s),thepowerdifferencebetweenthemainfrequencypowerandthe≧adjacentfrequencyissmallerthanthatofbubblingbottletransitionfluidization.Keywords:gas-solidtwo-phaseflow;flowcharacteristics;pressurepulsation;powerspectraldensities(PSD)目录1绪论.....................................................................................................................................-1-1.1研究背景..............................................................
