A.M. Makasheva, V.P. Malyshev.
ABSTRACT
The aim of the research is to develop the temperature dependence of the dynamic viscosity for sodium fluoride. The relevance of the research is related to the insufficient knowledge of the nature of the viscous state and fluid flow, the scattered temperature dependences of the viscosity, the fragmentation and narrowness of the experimental determination of this characteristic and the impossibility of displaying it in the full temperature range of the liquid state, especially for melts.
The scientific novelty of the work consists in displaying the temperature dependence of the viscosity of a cluster and associate probabilistic mathematical model, the hierarchical structure of which is adequate to the physical nature of the aggregation of particles without taking into account their specific structure, but taking into account the change in the degree of their association with temperature.
The data were calculated on the basis of a new cluster and associate equation, which was derived in the framework of the concept of randomized particles. The calculated data are given in the temperature range from the melting point to the boiling point. It is shown that the degree of association of clusters with increasing temperature naturally decreases, equal on average to three to four-particle arrangement of clusters in an associate. The cluster and associate model is compared with the Frenkel’s equation in logarithmic coordinates. The approximation was carried out by two rectilinear dependences intersecting in the temperature range of 1500 K. The high correlation coefficient of the Frenkel and cluster and associate models indicates the functional nature of the relationship, mutual correspondence and complementarity of these models.
KEY WORDS:
Boltzmann’s distribution, dynamic viscosity, randomized particles, associate, cluster, sodium fluoride.
DOI: 10.31857/S0235010620050060