Flow models binary dispersions

There have been several attempts at models incorporating breakup and coalescence. Two concepts underlie many of these models binary breakup and a flow subdivision into weak and strong flows. These ideas were first used by Manas-Zloczower, Nir, and Tadmor (1982,1984) in modeling the dispersion of carbon black in an elastomer in a Banbury internal mixer. A similar approach was taken by Janssen and Meijer (1995) to model blending of two polymers in an extruder. In this case the extruder was divided into two types of zones, strong and weak. The strong zones correspond to regions... 

It is mentioned, although not used in the model evaluation by Enwald and Almstedt [40], that a much simpler closure for the binary turbulent diffusion coefficient has been derived by Simonin [123] by an extension of Tchen s theory. This simple closure has been used by Simonin and Viollet [124], Simonin and Flour [125] and Mudde and Simonin [100] simulating several dispersed two-phase flows. 

In the frame of equilibrium theory, which neglects mass transfer resistances and axial dispersion, true counter-current (TCC) adsorption model was employed in a series of efforts to obtain explicit expressions of the fluid to solid flow rate ratios, nij (j = l, - -4), for complete separation of binary mixtures [8-9, 20-23]. The operation condition of SMB was then determined based on the equivalence between SMB and TCC process by keeping constant the liquid velocity relative to the solid velocity in the two processes. In special, desorbent is usually nonadsorbable (or it is so weak that its adsorptivity is negligible) for enantiomeric separation, and explicit criteria were obtained [8] to determine the boundaries of the complete separation region in the space spanned by rrij j = 1, 4). It should be noted that the purity and yield of both components are 100 % in theory within the complete separation region. 

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