Homogeneous nucleation rate measurements for water over a wide range of temperature and nucleation rate

Abstract

An expansion cloud chamber was used to measure the homogeneous nucleation rate for water over a wide range of temperature from 230–290 K and nucleation rates of 1–106 drops cm−3 s−1. The comprehensive and extensive nature of this data allows a much more detailed comparison between theory and experiment than has previously been possible. The expansion chamber technique employs continuous pressure measurement and an adiabatic pulse of supersaturation to give the time history of supersaturation and temperature during the nucleation. The resulting drop concentration is determined using photographic techniques. The experimental observations are presented in tabular form and from them an empirical nucleation rate formula is determined: J=S2 exp[328.124−5.582 43T+0.030 365T2−5.0319E−5T3 −(999.814−4.100 87 T+3.010 84E−3 T2)ln−2S], where J is the nucleation rate in units of drops cm−3 s−1. S is the supersaturation ratio and T is the temperature in K.

Suppression of sub-surface freezing in free-standing thin films of a coarse-grained model of water

“…Therefore, both homogeneous and heterogeneous nucleation are important in determining cloud dynamics. On a molecular level, nucleation events-whether homogeneous or heterogeneous-generally occur at length (≈ 10 −9 m) and time (≈ 10 −9 s) scales that are not accessible to the existing experimental techniques, and there has only been success in measuring nucleation rates in narrow ranges of temperature without gaining any knowledge about the characteristics of the intermediate states [11][12][13][14][15][16][17][18][19][20][21][22].…”

Scaled models for nucleation

“…Anderson and Kassner for water [39,40] and of Schmitt, Adams and Zalabsky for toluene [41] and nonane [42]. The expansion chamber data appear to be consistent with the […”

“…Finally, it seems appropriate to note that the expansion chamber data of Kassner, Miller and Anderson [39,40] and of Schmitt et al, [47,41] offer stringent tests for the temperature dependence of the theory, and it is unfortunate that this data has been so long overlooked. …”

A Monte Carlo discrete sum (MCDS) nucleation rate model for water

“…In fact, this is easy to FIGURE 1. Comparison of the experimental nucleation rate data [1][2][3] with the classical model prediction. verify as when one sets the classical prefactor equal to a constant, the above data of Viisanen et al do indeed fall on a line.…”

“…The homogeneous nucleation rate data for water of Viisanen et al [1] and Miller et al [2] , J exp (S,T), are plotted versus the classical model prediction for the nucleation rate, J class (S,T), in Fig. 1.…”