Xiuli Wang, Xiao Xu, Yuanyuan Zhao, Qiang Fu, JianenYu, and Wei Xu. Molecular Mathematical Modeling and Dynamics of Liquid Water Cavitation Inception Based on Copper and Platinum Wall Surfaces. Dynamic Systems and Applications 29 (2020) No. 11, 3287 – 3305
https://doi.org/10.46719/dsa2020291111
ABSTRACT:
In order to study the inception cavitation of liquid water, especially the microscopic influence of liquid cavitation of solid-liquid interface, in this paper, the SPC/E water molecular model was selected and the simulation method of molecular dynamics was applied, the formation of cavitation bubbles in liquid water was studied by stretching the walls of the system under the NVT ensemble. By comparing the cavitation effects of wall stretching of different metals (copper and platinum) on the water molecular system, the cavitation inception process, the development and change of cavitation bubble, the diffusion coefficient of water molecules, the function of radial distribution was analyzed. The results show that: the cavitation inception process of the water molecular system of copper and platinum wall is essentially the heterogeneous nucleation phenomenon on the metal surface; In low or high temperature state, the liquid water system of metal wall is not prone to the occurrence of cavitation inception phenomenon; In the process of studying the development and change of the cavitation bubbles of the water molecular system, the force field constraint of the copper wall system is more stable than that of the platinum wall surface system; The diffusion coefficient of water molecules in the copper wall system is larger than that of the platinum wall system, its internal diffusion rate is relatively fast, and the concentration degree is not obvious; The diffusion rate of water molecules with higher temperature is generally faster than that of the lower temperature system, and temperature change has a certain effect on the peak intensity of near-range orderly distribution around water molecules.
Keywords: Cavitation Inception; Cavitation Bubble; Molecular Dynamics Simulation; Diffusion Rule; Radial Distribution Function.