Hydrodynamics and Mixing

If, besides hydrodynamics and mixing, we want to consider other phenomena, such as a chemical reaction, we have to separate the probabilities characterizing each particular phenomenon ... 

A number of hydrodynamics and mixing models have been reported in the literature and are reviewed by Joshi and Shah (36). Future work should include the testing of these models for large columns. 

Joshi, J. B. Shah, Y. T. "Hydrodynamic and Mixing Models for Bubble Column Reactors," paper presented at ACS Las Vegas Meeting, August 1980. 

Pruvost J, Pottier L, LegrandJ Numerical investigation of hydrodynamic and mixing conditions in a torus photobioreactor, Chem Eng Sd 61(14) 4476-4489, 2006. 

Haque, M.W., Nigam, K.D.P, and Joshi, J.B. (1986), Hydrodynamics and mixing in highly viscous pseudo-plastic non-Newtonian solutions in bubble columns, Chemical Engineering Science, 41(9) 2321-2331. 

The high resolution images acquired with the high speed camera were used for the measurements of the hydrodynamics and mixing characteristics as discussed in Sect. 3.5.1.2. A script that allocates the plugs in an initial position and renames the files so they can be used in Insight 4G is presented. 

Tsaoulidis D., Li Q., Angeli, P., 2013. Hydrodynamics and mixing characteristics in small channels using ionic liquids for spent nuclear fuel reprocessing applications. In proceedings of the 8th International Conference on Multiphase How, Jeju, Korea, May 26-31... 

The design, scaleup and performance prediction of slurry reactors require models which must consider not only the hydrodynamic and mixing behavior of the three phases, but also the mass transfer between the phases along with the intrinsic kinetics. In the DCL and FTS processes, an axial dispersion model is applicable, with the solid phase assumed to follow sedimentation or dispersed flow model. However, in the CCC, where the solid particles take part in the reaction, dispersion model is no longer applicable. 

The fact that vegetable oils are generally liquid or fluid at room temperature allows them to be readily applicable in lubrication processes where formation of thick lubricant films is necessary. As described above, formation of high lubricant film thickness is important in processes that occur in hydrodynamic and mixed-film regimes. Thus, vegetable oils are suitable for formulating lubricants that will be applied in hydrodynamic and mixed-film regimes. 

Vegetable oils are considered functional fluids, since they have the ester functional group(s) and are also a liquid at room temperature. Such a property allows vegetable oils to be considered for a variety of applications where both functionality and fluidity are important. One such application area is lubrication, where vegetable oils, due to their functional fluid characteristics, have the potential to be applied in processes occurring in all lubrication regimes boundary, hydrodynamic, and mixed. 

A complicated bubble hydrodynamics and mixing patterns require special development efforts for process scaleup. 

Chesonis DC, Klinzing GE, Shah TT, Dassori CG. Hydrodynamics and mixing of solids in a circulating fluidized bed. Ind Eng Chem Res 29 1785 1792, 1990. 

The intensive mixers mentioned above are illustrated in Figure 9.3, together with others proposed in the literature in general they have been well characterized in terms of internal hydrodynamics and mixing performances, either by flow visualization techniques or using chemical methods, by mixing sensitive competitive reaction schemes computational fluid dynamics also supplied much information. 

Unfortunately, the available test rig is not capable to measure friction coefficient over the complete velocity range. Therefore it was not possible to verify all calculated points of the curve at this time. Nevertheless, one can see that in case of the lapped surface, the friction coefficient starts to increase after the hydrodynamic and mixed friction region is passed. However, in case of the polished surface, the friction coefficient is further decreasing. The reason is that no additional plastically deformed asperity will be added with decreasing velocity because of the smoothness of the polished surface. 

Rohde, S.M., "A Mixed Friction Model for Dynamically Loaded Contacts with Application to Piston Ring Lubrication", Surface Roughness Effects in Hydrodynamic and Mixed Lubrication, ed. S.M. Rohde and H.S. Cheng, ASME pub., 1980, pp. 19-50... 

Sivaiah M, Majumder SK (2013) Hydrodynamics and mixing characteristics in an ejector-induced downflow slurry bubble column (EIDSBC). Chem Eng J 225 720-733... 

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