Viva progress and development!
In modeling of multicomponent multiphase flow with phase transitions
the spatial distribution of phases and their properties (composition, pressure, velocity) are usually unknown from the beginning: this information must be extracted from the full
solution of the hydrodynamic problem. This makes difficult the application of the classical
Navier-Stokes model. Indeed, if the geometry of phases is unknown, then it is also unknown,
what viscosity coefficient must be put in Navier-Stokes equation in the given point of space.
Also, there is a difficulty in formulation of the conditions at the interfacial surface:
the Laplace condition presupposes the smoothness of the surface, and this absolutely excludes
the well known phenomena of division or coalescence of fluid droplets or gas bubbles.
These problems
are solved
in the density functional theory, which describes the multicomponent
multiphase mixture continuously without density jumps and
interfacial surfaces.
This is achieved by the introduction into the Helmholz energy or
into the entropy the square component density gradient terms.
As a result the hydrodynamics of multiphase mixture is
described in a unified way meaning the governing system of equations is the same at any space point.
The density functional approach possesses the following advantages:
it takes account of the structure of the interfacial region and of the surface layers
the surface tension coefficients are calculated from other parameters of the model
the model describes phase transitions and the flow simultaneously including the formation and the decay of phases, the condensation and the evaporation near solid surfaces
the model is indifferent to the complexity of the spatial geometry of the considered phases.
Examples of multiphase flow movies video/text
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Results from our archive
References to new papers and a book were added
Flow movie 'Motion of solid (elastic) body in a viscous flow passing around immobile obstacles'
Flow movie! '3D streamline of sphere with two-phase flow in gravity field'
Flow movie! 'Spinodal decomposition of three-phase three-component mixture'
Reference to the new paper "Modeling of multicomponent multiphase mixture flows on the basis of the density-functional method" was added
Section "Multiphase isothermal flow with presence of solid phase" was added
Flow movie 'Induced straight motion of solid body in a channel with viscous flow'
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