[01] Rehena Nasrin, Department of Mathematics, Bangladesh University of Engineering& Technology, Dhaka-1000, Bangladesh.

This paper analyzes numerically the effect of double-diffusive forced convection of fluid in a tubular chemical reactor. The model provides a study of an elementary, exothermic, 2nd-order reversible reaction in a tubular reactor (liquid phase, laminar flow regime). The aim of this project is to study numerically the effect of convective Heat and Mass transfer flow of a viscous fluid in the reactor. Assuming that the variations in angular direction around the central axis are negligible makes it possible to reduce the model to a 2D axisymmetric model. The governing equations namely mass, momentum, energy and material conservation equations are solved by Finite Element Method using Galerkin’s weighted residual scheme. The effects of rate of reaction and heat of reaction on the flow pattern and heat and mass transfer have been depicted. Comprehensive average Nusselt and Sherwood numbers, average temperature and concentration and mean subdomain velocity of the tubular reactor are presented as functions of the governing parameters mentioned above. Code validation is also shown with the results available in the literature.

Tubular Reactor, Heat-Mass Transfer, Finite Element Method

[01] Brown, N. and Lai, F., Correlations for combined heat and mass transfer from an open cavity in a horizontal channel, Int. Commun. in Heat and Mass Transf., Vol. 32, No. 8, pp. 1000–1008, 2005. [02] Parvin S., Nasrin R., Alim, M.A. and Hossain, N.F., Double-diffusive natural convection in a partially heated enclosure using a nanofluid, Heat Transf. - Asian Res., 41, No. 6, pp 484-497, 2012. [03] Muthucumaraswamy, R., Ganesan, P., Effect of the chemical reaction and injection on flow characteristics in an unsteady upward motion of an isothermal plate, J. Appl. Mech. Tech. Phys., Vol. 42, pp. 665-671, 2001. [04] Das, U.N., Deka, R., Soundalgekar, V.M., Effects of mass transfer on flow past an impulsively started infinite vertical plate with constant heat flux and chemical reaction, Forsch. in Ingenieurw., Vol. 60, pp. 284-287, 1994. [05] Chamka, A.J., MHD flow of a numerical of uniformly stretched vertical permeable surface in the presence of heat generation/absorption and a chemical reaction, Int. Commun. In Heat and Mass Transf., Vol. 30, pp. 413-22, 2003. [06] Ibrahim, F.S., Elaiw, A.M., Bakr, A.A., Effect of chemical reaction and radiation absorption on the unsteady MHD free convection flow past a semi infinite vertical permeable moving plate with heat source and suction, Comm. in Nonlinear Sci. and Num. Simul., Vol.13, pp. 1056-1066, 2008. [07] Kesavaiah, DC.H., Satyanarayana, P.V. and Venkataramana, S., Effects of the chemical reaction and radiation absorption on an unsteady MHD convective heat and mass transfer flow past a semi-infinite vertical permeable moving plate embedded in a porous medium with heat source and suction. Int. J. of Appl. Math. and Mech., Vol. 7, No. 1, pp. 52-69, 2011. [08] Koning, B., Heat and mass transport in tubular packed bed reactors at reacting and non-reacting conditions, Ph.D. Thesis, University of Twente, Netherland, 2002. [09] Kugai, J.,Heat and mass transfer in fixed-bed tubular reactor, May 1st 2008, 2008. [10] Frolov, S.V., Tret’yakov, A.A. and Nazarov, V.N., Problem of optimal control of monomethylaniline synthesis in a tubular reactor, Theore. Found. of Chem. Engg., Vol. 40, No. 4, pp. 349–356, 2006 [11] Nijemeisland, M., Dixon, A.G. and Stitt, E.H., Catalyst design by CFD for heat transfer and reaction in steam reforming, Chem. Engg. Sci., Vol. 59, pp. 5185-5191, 2004. [12] Rostrup-Nielsen, J.R., Sehested, J.and Norskov, J.K., Hydrogen and synthesis gas by steam- and CO2 reforming, Adv. Catal, Vol. 47, pp. 65-139, 2002. [13] Kvamsdal, H.M., Svendsen, H.F., Hertzberg, T.and Olsvik, O., Dynamic simulation and optimization of a catalytic steam reformer, Chem. Engg. Sci., Vol. 54, pp. 2697-2706, 1999. [14] Dixon, A.G. and Nijemeisland, M., CFD as a design tool for fixed-bed reactors, Ind. Engg. Chem. Res., Vol. 40, pp. 5246-5254, 2001. [15] Dixon, A.G. and Cresswell, D.L. Theoretical prediction of effective heat-transfer parameters in packed-beds, Aiche. J., Vol. 25, pp. 663-676, 1979. [16] Bunnell, D.G., Irvin, H.B., Olson, R.W. and Smith, J.M., Effective thermal conductivities in gas-solid systems,Ind. Engg. Chem., Vol. 41, pp. 1977-1981, 1949. [17] Nijemeisland, M. and Dixon, A.G., Comparison of CFD simulations to experiment for convective heat transfer in a gas-solid fixed bed, Chem. Engg. J., Vol. 82, pp. 231-246, 2001. [18] Dixon, A.G. and Cresswell, D.L., Estimation of heat-transfer parameters in packed-beds from radial temperature profiles - Comment, Chem. Engg. J. Bioch Engg., Vol. 17, pp. 247-248, 1979. [19] Gladden, L.F., Recent advances in MRI studies of chemical reactors: ultrafast imaging of multiphase flows, Top Catal., Vol. 24, pp. 19-28, 2003. [20] Masoumi, M.E., Sadrameli, S.M., Towfighi, J. and Niaei. A.,Simulation, optimisation and control of a thermal cracking furnace, Energy, Vol. 31, p516–527, 2006. [21] Gladden,L.F., Mantle, M.D. Sederman,A.J. and Yuen, E.H.L., Magnetic resonance imaging of single- and two-phase flow in fixed-bed reactors, Appl. Magn. Reson., Vol. 22, pp.201-212, 2002. [22] Ziolkowska, I. and Ziolkowski, D., Modelling of gas interstitial velocity radial distribution over cross-section of a tube packed with granular catalyst bed; effects of granule shape and of lateral gas mixing" Chem. Engg. Sci., Vol. 62, pp. 2491-2502, 2007. [23] Logtenberg, S.A. and Dixon, A.G., Computational fluid dynamics studies of fixed bed heat transfer, Chem. Engg. Process, Vol. 37, pp. 7-21, 1998. [24] Dixon, A.G., Nijemeisland, M.and Stitt, E.H., CFD study of heat transfer near and at the wall of a fixed bed reactor tube: Effect of wall conduction, Ind. Engg. Chem. Res., Vol. 44, pp. 6342-6353, 2005. [25] Taskin, M.E., Dixon,A.G. and Stitt, E.H., CFD study of fluid flow and heat transfer in a fixed bed of cylinders, Numer. Heat Transf.-Appl., Vol. 52, pp. 203-218, 2007. [26] Nasrin, R. and Alim, M.A.,Semi-empirical relation for forced convective analysis through a solar collector, Solar Energy, Vol. 105, pp. 455-467, 2014. [27] Zienkiewicz, O.C. and Taylor, R.L., The finite element method, Fourth Ed., McGraw-Hill, 1991. [28] Taylor, C., Hood, P., A numerical solution of the Navier-Stokes equations using finite element technique, Computer and Fluids, Vol. 1, pp. 73–89, 1973. [29] Dechaumphai, P., Finite element method in engineering, 2nd ed., Chulalongkorn University Press, Bangkok, 1999.