In this chapter, we describe the crystallizations of the supercooled droplets of the
emulsion but we take into account the corresponding released energy. It is sufficient to
warm up the emulsion at a temperature sufficiently high to be in a range where the
nucleation rate vanishes stopping the crystallizations. So, we observe a local self-regulation
of the temperature. On the contrary, the melting of the crystallized droplets occurs when the
local temperature induces the thermodynamic equilibrium. These phases transforms are
shown whether on a cylinder about 500 cm3 in volume or by calorimetry experiments on
smaller samples. Models are presented to explain in all cases the observed phenomena.
They are based on the resolution of the equation of the heat conduction with a heat source
proportional to the probability of crystallization, given by the nucleation laws, and to the
number of the remaining unfrozen droplets. In the particular case of a high concentrated
emulsion of water, it is demonstrated the possibility of seedings increasing the number of
crystallizations. Different methods are presented to determine the nucleation rate function
and, in particular, a characterization by an inverse method. We describe also the case of
emulsions flowing in a pipe. We mainly treat the case of the pure substances, but the case
of binary solutions is approached.
Keywords: Binary solutions, calorimetry, crystallization, emulsions, flows, heat
transfers, melting, seeding, self-regulation, supercooling.
