Abstract：Due to the limitations of sampling and measurement techniques, there is a lack of in-depth study on the migration and aggregation behavior of water at the interface between mineral oil and cellulose. In this paper, the migration and aggregation of water molecules at the interface between mineral oil and cellulose during heating process were studied from the molecular level. A model of a 105 atomic-scale mineral oil and cellulose composite media was established. The heating process from 293K to 353K was simulated. The aggregation state, diffusion coefficient, free volume, and radial distribution function of water molecules were calculated and analyzed, and the effects of electric and temperature fields in this process were compared. The results show that when the moisture in cellulose exceeds 4%, rapid temperature rise will cause water molecules to accumulate into clusters of water molecules through intermolecular hydrogen bonding at the oil-paper interface to form local liquid water. When the moisture content exceeds 5%, a large liquid water zone will be formed. The polarization of the electric field enhances the hydrogen bonding forces, increases the probability of appearance of high water partitions, decreases the diffusion coefficient and free volume of water molecules, and presents anisotropy in its diffusion coefficient.
王伟, 董文妍, 李芳义, 蒋达, 宁中正. 升温过程中水在矿物油和纤维素界面扩散和聚集行为的分子模拟[J]. 电工技术学报, 2019, 34(17): 3696-3704.
Wang Wei, Dong Wenyan, Li Fangyi, Jiang Da, Ning Zhongzheng. Molecular Simulation of the Diffusion and Aggregation of Water at the Interface between Mineral Oil and Cellulose during Temperature Rising. Transactions of China Electrotechnical Society, 2019, 34(17): 3696-3704.
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2019, Vol. 34 
