Phenomenological model of homogenous condensation

Puzyrewski, Romuald
August 2000
AIP Conference Proceedings;2000, Vol. 534 Issue 1, p303
Academic Journal
Molecular effects govern nucleation and condensation phenomena. Due to the high complexity of treating such a phenomena on molecular level, the phenomenological approach seems to bridge the gap between the real scale of nucleation and condensation and technical needs for a simpler model. Accuracy in comparisons with experimental data can be achieved within the frame of phenomenological models by means of proper definition and reliable values of coefficients, which describe the process of nucleus creation, rate of nucleation and growth of nuclei up to the droplets of macroscopic size. The paper presents the rearrangement of classical Becker-Döring (BD) equation into the form of Fokker-Planck-Kolmogorow equation (F-P-K) where nucleus growth plays an important role. The set of equations for the nuclei growth is discussed. The well known Volmer-Frenkel (V-F) nucleation rate can be derived from the master F-P-K equation for isothermal nucleus growth. It has been shown that nonisothermal growth of nucleus deviates from isothermal one.


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