Abstract
The coalescence of drops, larger than microscale vortices, induced by velocity pulsations in concentrated emulsions is examined based on the theory of locally isotropic turbulence.
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Abbreviations
- n:
-
number of drops per unit volume of emulsion
- t:
-
time
- λ0 and L:
-
micro- and macroscales of turbulence
- ρe, ρc, and ρd :
-
densities of the emulsion, the continuous, and the disperse phases, respectively
- σ:
-
interphase tension
- W:
-
concentration of the dispersed phase
- DT :
-
diameter of the agitating turbine
- N:
-
rate of rotation of the turbine
- D and H:
-
diameter and height of the mixing volume
- d32 :
-
averaged volume-surface diameter of the drops
- dm :
-
maximum size of drops that are stable with respect to fragmentation
- f(W):
-
concentration dependence
- ¯v and ¯v(W):
-
averaged magnitudes of the pulsation velocity in finely dispersed and coarsely dispersed emulsions
- ¯gq and θ:
-
rates of collisions and coalescence of drops
- tc and θc :
-
time and rate of circulation
- ReM :
-
Reynolds number of mixer
- μe :
-
effective viscosity of the emulsion
- Kv :
-
constant describing the efficiency of collisions drops induced by velocity pulsations
- Fv(W) and Fg(W):
-
functional relations between the rate of coalescence and concentration of drops in the inertial and gradient regimes
Literature cited
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Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 42, No. 1, pp. 27–33, January, 1982.
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Rozentsvaig, A.K. Coalescence of coarsely dispersed concentrated emulsions with turbulent agitation. Journal of Engineering Physics 42, 19–24 (1982). https://doi.org/10.1007/BF00824984
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DOI: https://doi.org/10.1007/BF00824984