ABSTRACT
Nomenclature ..................................................................................................................... 581
References .......................................................................................................................... 583
Mixing is an important unit operation in processing operations, which is used for purposes
that include blending of ingredients, improvement of the rate of heat transfer, facilitation of
chemical reactions, creation of structure, the addition of energy to create or break molecular
bonds, etc. Turbulent mixing of low-viscosity liquids and gases works quickly because it
mainly uses the mechanisms of distributive mixing and molecular diffusion in chaotic turbu-
lent eddies. These eddies are superimposed on the mean flow pattern and scale from the size of
the mixing element down to the molecular level [1,2]. The mixing of highly viscous fluids is
more difficult because it generally takes place only in the laminar regime and mainly involves
the mechanisms of laminar shear, elongational flow, and distributive mixing to reduce the
scale of segregation, whereas molecular diffusion (which occurs very slowly) and dispersion
act to reduce the intensity of segregation [2,3].
