
Numerical simulations of solute Taylor dispersion of separated flows in capillaries
LI Xiang;LIU Hui
Journal of Beijing University of Chemical Technology ›› 2009, Vol. 36 ›› Issue (s1) : 8-13.
Numerical simulations of solute Taylor dispersion of separated flows in capillaries
Computational fluid dynamics (CFD) numerical simulations were carried out to compute the axial diffusion coefficient (Dz) of the solute Taylor dispersion in single-phase separated flows in capillaries. The effects of the liquid velocity, unit cell length, film thickness, film length, the diameter of capillary, and the number of unit cell were investigated. The results of simulation indicate that under the condition of Re between 750 and 1950 the Dz values is increasing with increasing values of liquid velocity, unit cell length and the number of unit cells. When the diameter of capillary between 2 and 5mm, the Dz values is increasing with increasing values of the diameter; when the diameter of capillary large than 5mm, the increasing current of Dz become slowness. The Dzvalues is independent of film thickness and film length.
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