6506

6071

كارشناسي ارشد

مهندسي شيمي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مهندسي شيمي

1390

هفده، 127ص.: مصور، جدول، نمودار

ص.ع. به فارسي و انگليسي

محمدرضا احساني

مسعود حق شناس فرد

3/12/90

محسن نصراصفهاني، ابراهيم شيراني

1396/10/12

كتابنامه

مهندسي شيمي

مهندسي شيمي

ID6071

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Simulation Hydrodynamic and Mass Transfer in the Packed Bed with Spherical Particle Rahim Golafshan R golafshan@ce iut ac ir 2011 07 09 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor M R Ehsani ehsanimr @cc iut ac irAbstractA new method is presented to couple the fluid flow in a fixed bed to the mass transfer and physicaladsorption inside a catalyst particle using computational fluid dynamics CFD To this end in thisresearch the momentum and mass transfer equations over a single sphere along with appropriateboundary conditions on the sphere and also mass transfer equation inside the particle is simulatedsimultaneously with commercial software Fluent 6 3 26 A user defined function UDF is used todetermine the particle wall boundary conditions on the catalyst Hence the normal velocity componenton the fluid solid interface is computed using mass flux across the solid boundary To validate the result dimensionless Sherwood number around the spherical particles are compared Also The variation ofSherwood number versus angle from stagnation point is reviewed and breakthrough curve is showedqualitatively and also the effect of velocity and mesh size in diagrams is presented The results showthat this model can be used to simulate the adsorption for porous media Path line velocities andconcentration profiles show that commonly used models of porous media can not present an exactsolution to the porous media problem due to their significant simplifications Next step the packed bedFor 8 14 layout and three types of 20 layout DEM method is analyzed and simulated The contoure ofPressure and velocity is analyzed and the pressure drop result is compared with empiricalcorrelation On the other hand the effect of Reynolds number in pressure drop diagram for packed bedwith 14 20 layout is showed Also the results showed pressure drop in random packing is higher thanthe ordered packing The velocity vector and contoure of pressure in different wall segment and Renoldsnumber is indicated The result suggest that Velocity magnitude in near the wall is increased and theincrease of Reynolds number leads to increase the possibility of eddy formation that caused reverseflow in outlet Also the increase of Reynolds number leads to growth radial velocity near the wall morethan the center of packed bed This eddy leads to increase velocity more than the inlet velocity Thiscondition influenced on mass and heat transfer coefficient strongly Finally the momentum and masstransfer equation for fluid and solid phase and also physical adsorption for packed bed with 8 layout issolved Since Lack of laboratory results for this type of geometry and also impossible conditions to testthe experiment the result and breakthrough curve is analyzed qualitatively The results is showed thatthe consentration profile in the particle is depended on radius and angular strongly This profile is notsymmetric On the other hand this profile is showed that the assumption of LDF model is establishedwhen the velocity field around the sphere is fully development At the end of this project the result isshowed that usage of parameters such as bed void and specific area can not predict correctly the masstransfer coefficient and flow field Key Words computational fluid dynamics mass transfer adsorption porous media

محمدرضا احساني

مسعود حق شناس فرد

محسن نصراصفهاني، ابراهيم شيراني