| Blends
and emulsions are formulated in various types of dispersing apparatus.
In a typical approach these devices are considered as Black Boxes where
an intergral measure of the dispersing and form conservative forces are
acting. For example, in the typical Capillary Number versus Viscosity
Ratio plot only statical material parameters such as the viscosity of
the contineuous phase, the acting shear rate and the time invariant
interfacial tension are used to calculate the dispersing process as a
sum function. Within this approach considerable knowledged is gathered
to tune and optimize dispersing and mixing devices. However, the
individual history of one particle or droplet traveling through such
device is unknown and as a consequence, one is not able to fine-tune
the Black-Box in respect to well-defined deformation and breakup. As an
example one may consider a emulsion systems; in one arbitrary moment of
time the size, size distribution, interface tension of the system well
defined and static. Once the system is able to develop in time,
structures and interacting forces will lead to a dynamic system of a
non-equilibrium character. Where all parameter are a function of time
and flow field. As a consequence, the deformation, and breakup occuring
in such system are a complex interaction amoung size, time, flow field,
and interfacial properties. The dynamic interplay of these parameters
is subject of the research project Deformable Interfaces - Multiphase
Flow where we like to gain more understanding of such dispersing
processed with the help of fluid visuasization, interfacial rheology,
and CFD. |
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