Molecular-dynamic simulation of water vapor interaction with suffering pores of the cylindrical type

E. G. Nikonov; M. Pavluš; M. Popovičová

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arXiv · 1805.02461

Molecular-dynamic simulation of water vapor interaction with suffering pores of the cylindrical type

E. G. Nikonov·M. Pavluš·M. Popovičová

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Abstract

Theoretical and experimental investigations of water vapor interaction with porous materials are carried out both at the macro level and at the micro level. At the macro level, the influence of the arrangement structure of individual pores on the processes of water vapor interaction with porous material as a continuous medium is studied. At the micro level, it is very interesting to investigate the dependence of the characteristics of the water vapor interaction with porous media on the geometry and dimensions of the individual pore. In this paper, a study was carried out by means of mathematical modelling of the processes of water vapor interaction with suffering pore of the cylindrical type. The calculations were performed using a model of a hybrid type combining a molecular-dynamic and a macro-diffusion approach for describing water vapor interaction with an individual pore. The processes of evolution to the state of thermodynamic equilibrium of macroscopic characteristics of the system such as temperature, density, and pressure, depending on external conditions with respect to pore, were explored. The dependence of the evolution parameters on the distribution of the diffusion coefficient in the pore, obtained as a result of molecular dynamics modelling, is examined. The relevance of these studies is due to the fact that all methods and programs used for the modelling of the moisture and heat conductivity are based on the use of transport equations in a porous material as a continuous medium with known values of the transport coefficients, which are usually obtained experimentally.

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E. G. Nikonov, M. Pavluš, M. Popovičová. 2018-05-07. Molecular-dynamic simulation of water vapor interaction with suffering pores of the cylindrical type. https://arxiv.org/abs/1805.02461

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