化工传递过程原理课件：第八multicomponet (II)_149001709

1、Generalized Maxwell-Stefan Equation MMiiitiitiitiiCC xC xC xNvvvJvJMMijjiijjiijjiij ij ij itijtijtijxxxxxxC DC DC DNNJJJJdlniiiiiiiixxRTxVPFZRTRT d10nMiiJ10niiiixJ10niiiN1nikiikinikk ixxBDD11ijiinijBxDD 1MtC BJd 1xtCBBJdxknikikiknBxxx 1tCBNd1nikikiknjjjxxMulticomponent mass transfer driven by severa

2、l driving forces ()() IBIAISCCRNvNvn 1tCBNd VCRtNCase I: Mole Fraction Gradient with No FluxThe system is at steady.The gas is ideal, isothermal and isobaric.It is desired to determine xC (y) . 011expsCCACBCtR yxyxDDCSASRR Discrete Maxwell-Stefan EquationFor the one dimension problem in a thin film0

3、iiiiiiiixdxxdRT dyRTRT ln(ln()()iiiiiiiiiiiidxxxxdxxdyx *PiiiiiiixxxdPPPdVVRTdyRTP *iiRTPV*iiiiiiixxxddFZFZRTdyRT *iiRTFZ *iiiiiiiixxPdxP *1njiiijjiiiiijj ivvxPxxPk*11nijjiiijiiiitiijj ix Nx NxPxPC xkijijDk1,2,itiiNC x vin1njiiijjijj ivvfx xD10niiiNSteady, no homogeneous reaction and one dimension p

4、roblems in a rectangular coordinate systemCase II: The condensation of a gas mixture122113311121321122332212233110ttx Nx Nx Nx NxCkkx Nx Nx Nx NxCkkNCase III: Gas diffusion with Heterogeneous Reaction511110548SSPPaTKRk C To estimate the overall rate of the reaction of ethanolijijkD1213230.070.230.23

5、kkk1020300.70.150.15xxx10.45skThe solution of the differential equations yieldsThe solution of the discrete equations yields10.996N 10.959N M-S approach for electrolytesKey points:1. Species: ions and solvent molecules2. Electroneutrality relation3. Bootstrap equation4. Electric driving force (impor

6、tant) 0iiiZ x iiiFZINln()ijjiiiij itiijxxRTRTxFZC xDNNLFor dilute solution of stagnant water lniiitiiwFZxRTC x D NL*iiitiiwxNxC xk For dilute solution of stagnant water*1ijjiiij iiiitiijx Nx NxxC xkFor the one dimension problem inside a thin film: steady and no homogeneous reaction in a rectangular

7、coordinate systemat room temperature40iiiitiiwxNZxC xk 1112()ABAwBwDDDPolarization in electrolysisM-S equations:bootstraps:12xxx320NN113txFNxRTC xk 0 xFxRT RTxFx 1132tFNC xkRT Limiting current when:1022/20 xxRTFVx 0 13212tFRTIFC x kFRT 012xxFRTlim0 132tIFC x klim12FIRTFIRT01212FRTxxFRT 0 xat room temperature专题报告Maxwell-Stefan 方法在传质过程模型化中的应用1.近期国际刊物文献(不能是review) .2.选择自己感兴趣的主题，限于Maxwell-Stefan 方法。3.精读：详细推导其