Molecular dynamics simulation of water diffusion in mixed insulating oil at different temperatures

Abstract

The effects of temperature and moisture on the mixed insulating oil micro-characteristics were investigated by molecular simulation. In order to analyse the mechanism of action between insulating oil and water molecule, the mixed insulating oil model consisting of mineral oil and natural ester with different mass ratio and different moisture content was established. Through the research of hydrogen bonding, radial distribution function (RDF) of oil molecules and the diffusion coefficient of water molecules, it shows that the higher the natural ester content in the model, the more the number of hydrogen bonds, the bigger the peak value of RDF, the smaller the diffusion coefficient of water molecules. At the same time, the increase of temperature weakened the binding effect of mixed insulating oil on water molecules, and the increase of water content enhanced the ability of mixed insulating oil and water molecules to form hydrogen bonds. The final results showed that different natural ester content enhanced the thermal stability and insulation characteristics of the mixed insulating oil.