2019年 反应工程基础(程易)chapter10-model nonideal reactorsppt课件.ppt

《2019年 反应工程基础(程易)chapter10-model nonideal reactorsppt课件.ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、NonidealFlowCharacterizedbyResidenceTimeDistribution(RTD)PulseinputoftracerF(t)RTD-方差的加和性一次矩的加和性二次矩的加和性[s][s2]假设界面处无返混(小)有对矮胖反应器：端部的返混贡献很大对细长反应器：端部返混贡献可忽略E1E2E3卷积（E(t):传递函数的概念）Chap9-Summary1.E(t)dt:fractionofmaterialexitingthereactorthathasspentbetweentimetandt+dtinthereactor.2.Themea

2、nresidencetime3.Thevarianceaboutthemeanresidencetimeisisequaltothespacetimeforconstantvolumetricflow,=04.ThecumulativedistributionfunctionF(t)givesthefractionofeffluentmaterialthathasbeeninthereactoratimetorless:5.TheRTDfunctionsforanidealreactorarePlugflowCSTRLaminarflow6.Thedimen

3、sionlessresidencetimeis7.Theinternal-agedistribution,[I(),],givesthefractionofmaterialinsidethereactorthathasbeeninsidebetweenatimeandatime+d（自学，P633－634）***SimplediagnosticsandtroubleshootingusingtheRTDforidealreactors***8.SegregationmodelFormultiplereactions9.Maximummixedness:F

4、ormultiplereactions***迟混与早混（见网络学堂补充材料）***O.Levenspiel,P358(a)(b)(c,d,e)Chapter10ModelsforNonidealReactorsOverviewUsetheRTDtoevaluateparametersModelofreactorflowpatternsTanks-in-seriesmodelDispersionmodel10.1SomeguidelinesRTDdata+Kinetics+Model=PredictionGuidelinestodevelopmodelsforno

5、nidealreactors1.Themodelmustbemathematicallytractable.2.Themodelmustrealisticallydescribethecharacteristicsofthenonidealreactors.Thephenomenaoccurringinthenonidealreactormustbereasonablydescribedphysically,chemically,andmathematically.3.Themodelmustnothavemorethantwoadjustableparamete

6、rs.10.1.1One-parametermodelsNonidealCSTRsincludeareactordeadvolumeVD,noreactiontakesplaceNonidealCSTRswithafractionoffluidbypassingthereactor,exitingunreactedTanks-in-seriesmodelDispersionmodel*ThisparameterismostalwaysevaluatedbyanalyzingtheRTDdeterminedfromatracertest.Examples:10.1.

7、2Two-parametermodelsC(t)tVsVD0bs010.2Tanks-in-series(T-I-S)model123PulseV1=V2=Vi=01=2=iFirstreactor:Secondreactor:ODE:Solution:Sametothirdreactor...nCSTRs:(C2=0att=0)RTDforequal-sizetanksinseries::Vtotal/n:calculatedfromRTDLevenspielbook(3rd)Firstorderreaction:E()n=10n=4n

8、=2n:n