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ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

MOLECULAR DYNAMICS STUDY ON EVOLUTION OF SODIUM VAPOR ON DUST PARTICLES SURFACE IN COOLING PROCESS

Get access (open in a dialog) DOI: 10.1615/IHTC16.nmt.023690
pages 7249-7256

Resumo

The evolution of metal vapor on dust particles surface has serious influences on the flue gas purification. In order to reveal the evolution mechanism of metal vapor on the surface of dust particles, the process of condensation and solidification of sodium (metal vapor) on the surface of silica (dust particles) was investigated by molecular dynamics simulations. The agglomeration, growth and diffusion behavior of sodium atoms during the phase transition process was examined. The density and temperature variations along the Z direction of the sodium-silica system during the cooling process were obtained, the scattering intensity and radial distribution function (RDF) of the system was analyzed from a microscopic point of view. It is found that as the temperature decreases, the aggregation of sodium atoms occurs mainly in the region near to surface, and with the decrease of temperature, the phase of sodium atom in the system begins to change, so aggregation of sodium atoms becomes more and more obvious. The diffusion coefficient decreases with the decrease of temperature, and there are two obvious turning point between the diffusion coefficient and temperature curve which indicates that the liquefaction and solidification temperature are in the vicinity of 498K and 398K respectively, and the values are basically consistent with the results analyzed by RDF. According to the difference between the scattering intensity, the state of the system can be roughly divided into three regions, which are 298-398 K, 398-498 K, and 498-698 K respectively, and they correspond to the solid, liquid and gaseous states of the system, respectively. And the scattering intensity increases as the temperature decreases on the whole.