A Study on the Effects of Thermodynamic Nonideality and Mass Transfer on Multi-phase Hydrodynamics Using CFD Methods

Considering non-ideal behavior of fluids and its effects on hydrodynamic and mass transfer in multiphase flow is very essential. Simulations were performed that takes into account the effects of mass transfer and mixture non-ideality on hydrodynamics reported by Irani et al. In this paper, by assuming the density of phases to be constant and Raullt-s law instead of using EOS and fugacity coefficient definition, respectively for both the liquid and gas phases, the importance of non-ideality effects on mass transfer and hydrodynamic behavior was studied. The results for a system of octane/propane (T=323 K, P =445 kpa) also indicated that the assumption of constant density in simulation had major role to diverse from experimental data. Furthermore, comparison between obtained results and the previous report indicated significant differences between experimental data and simulation results with more ideal assumptions.





References:
[1] Rigopoulos, S. , Jones, A. G., "A hybrid CFDÔÇöreaction engineering framework for multiphase reactor modelling: basic concept and
application to bubble column reactors", Chem.Eng.Sci, 58, 3077-3089(2003).
[2] Darmana, D., Henket, R.L.B., Deen, N.G., Kuipers, J.A.M.,"
Detailed modeling of hydrodynamics, mass transfer and chemical
reactions in a bubble column using a discrete bubble model: Chemisorption of CO2 into NaOH solution, numerical and experimental study", Chemical Engineering Science, 62, 2556 -2575(2007).
[3] Bauer, M., Eigenberger, G., "A concept for multi-scale modeling of
bubble columns and loop reactors", Chem.Eng.Sci. , 54, 5109-
5117(1999).
[4] Bauer, M., Eigenberger, G. , "Multiscale modeling of
hydrodynamics, mass transfer and reaction in bubble column
reactors", Chem. Eng .Sci. 56, 1067-1074(2001).
[5] Bezzo ,F., Macchietto ,S., Pantelides ,C. C., "A general methodology
for hybrid multizonal/CFD models Part I. Theoretical framework",
Computers and Chemical Engineering 28, 501-511 (2004).
[6] Zauner, R., & Jones, A. G. (2000). "Scale-up of continuous and batch
precipitation processes", Industrial and Engineering Chemistry
Research, 39(7), 2392-2403(2000).
[7] R Krishna, R., Van Baten, J.M., "CFD modeling of bubble column
reactor carrying out consecutive reaction (A۫BC)",
Chem.Eng.Thechnol, 27 (2004) 67-75.
[8] Breach, M.R., Ansari, N., "Modeling non-ideal vapor-liquid phase
equilibrium, mass and energy transfer in a binary system via
augmentation of computational fluid dynamical methods", Comput.
Chem. Eng., 31 1047-1054 (2007).
[9] Banerjee, R. ," Turbulent conjugate heat and mass transfer from the
surface of a binary mixture of ethanol/iso-octane in a countercurrent
stratified two-phase flow system", International Journal of Heat and
Mass Transfer ,51 (2008) 5958-5974.
[10] Hirt, C. W. , Nichols ,B. D., "Volume of Fluid (VOF) Method for
the Dynamics of Free Boundaries", J. Comp. Phys. 39, 201(1981).
[11] Irani, M., Bozorgmehry, R.B., Pishvaie , M.R. , Tavasoli, A., IJCCE
," Investigating the effects of mass transfer and mixture non-ideality
on multiphase flow hydrodynamics using CFD methods",2009.
[12] Treybal, R.E., "Mass Transfer Operations ", Third Edition, McGraw-
Hill, (2001).
[13] Smith, J.M, and Van Ness, H.C., "Introduction to Chemical
Engineering Thermodynamics", 6th Edition, McGraw-Hill, (2001).
[14] Walas, S.M," Phase equilibria in chemical engineering", Butterworth,
Storeham, USA (1985).
[15] Patankar, S.V., "Numerical Heat Transfer and Fluid Flow", Taylor
and Francis, (1980).