1205.0275 (Nikolay V. Alekseechkin)
Nikolay V. Alekseechkin
The multivariable theory of nucleation [J. Chem. Phys. 124, 124512 (2006)] is applied to the problem of vapor bubbles formation in pure liquids. The presented self-consistent macroscopic theory of this process employs thermodynamics (classical, statistical and linear non-equilibrium), hydrodynamics and interfacial kinetics. As a result of thermodynamic study of the problem, the work of formation of a bubble is obtained and parameters of the critical bubble are determined. The variables V (the bubble volume), \rho (the vapor density), and T (the vapor temperature) are shown to be natural for the given task. An algorithm of writing the equations of motion of a bubble in the space {V, \rho, T} - equations for V, \rho, and T - is offered. This algorithm ensures symmetry of the matrix of kinetic coefficients. The equation for written on the basis of this algorithm is shown to represent the first law of thermodynamics for a bubble. The negative eigenvalue of the motion equations which alongside with the work of the critical bubble formation determines the stationary nucleation rate of bubbles is obtained. Various kinetic limits are considered. One of the kinetic constraints leads to the fact that the nucleation cannot occur in the whole metastable region; it occurs only in some subregion of the latter. Zeldovich theory of cavitation is shown to be a limiting case of the theory presented. The limiting effects of various kinetic processes on the nucleation rate of bubbles are shown analytically. These are the inertial motion of a liquid as well as the processes of particles exchange and heat exchange between a bubble and surrounding liquid. The nucleation rate is shown to be determined by the slowest kinetic process at positive and moderately negative pressures in a liquid. The limiting effect vanishes at high negative pressures.
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http://arxiv.org/abs/1205.0275
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