Bubble and drop formation

Some industrial operations involving bubble and drop formation are extraction, direct contact heat exchange, distillation, absorption, sparger reactors, spray drying and atomization, fluidization, nucleate boiling, air lifts, and flotation. 

Equation (156) is applicable for both bubble and drop formation. Thus, when term (V) is negligible, it describes bubble formation for all fluids when surface tension is important. On further removal of term (IV), it applies for viscous liquids in the absence of surface tension. If only terms (I) and (II) are retained, the equation applies to the inviscid case without surface tension. 

The very important field of bubble and drop formation in non-Newtonian fluids remains virtually untouched, even in the absence of heat and mass transfer and chemical reactions. 

One of the major contributions from this group has been the development of a unified model, which could explain both bubble and drop formation through a single set of equations.This model has been tested for a variety of systems. It has been modified to take into account the complexities, drainage between bubbles, etc. New models have been developed for the prediction of drop and bubble sizes in complex situtations like sieve plates, sintered disks, etc. The model has been also extended to predict pneumatic atomisation, nucleate boiling, etc. 

Decomposition Procedures for the Solving of Large Scale Systems W. P- Ledet and D. M. Himmelblau The Formation of Bubbles and Drops R. Kumar and N. R. Kuloor Author Index—Subject Index... 

Kumar, R. and Kuloor, N.R., The formation of bubbles and drops. In Advances... 

In all these operations involving bubbles and drops, three stages have to be studied, viz. (i) the formation of bubbles or drops, (ii) the movement of bubbles or drops through the continuous phase and possible coalescence therein, and (iii) the formation of the interface. This review is an attempt to understand the first of the three aspects of the study, especially in the case of submerged orifices. 

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