Hygroscopic characteristics of salt particles based on molecular dynamics simulations

LX Zhan and X Wang and DW Hou and H Chen and SQ Zheng and YR Wang and ZH Li and ZX Chen and H Wu and LJ Yang, POWDER TECHNOLOGY, 455, 120787 (2025).

DOI: 10.1016/j.powtec.2025.120787

Molecular dynamics simulations are performed to investigate the hygroscopic growth of typical salt particles and their mixtures in supersaturated water vapor. Nucleation and condensational growth are analyzed. The results showed the dominant factors controlling the growth of the salt particle are condensation and collisions thereafter. The salt particles help to the hygroscopic growth. MgCl2 possesses the highest tendency of hygroscopicity. The self-diffusivity of water in the MgCl2 case (1.54 x 10_ 6 m2/s) is much smaller than that of the homogeneous case (2.23 x 10_6 m2/s). Radial distribution analysis (RDF) confirms the dissociation of ionic bonds and the formation of the hydration shell. Particle number concentration (PNC) and particle mass concentration (PMC) have different influence mechanisms on nucleation and growth. Moreover, the supersaturation degree is modified by changing the vapor pressure and temperature. Homogeneous nucleation is found to be more susceptible to changes in supersaturation than heterogeneous nucleation.

Return to Publications page