Molecular dynamics study on thermal decomposition characteristics of synthetic ester oil

Abstract

The synthetic ester oil has great application potential in liquid insulation of traction transformer due to its excellent insulation performance. In this paper, molecular dynamics simulations were performed using the ReaxFF reaction force field to study the thermal decomposition mechanism and product distribution of synthetic ester oils. The results show that the initial decomposition reaction is ester bond cleavage, followed by the decarboxylation reaction and β-C bond cleavage; the main decomposition products are CO2, C2H4 and some C2 and C3 species; by studying the effect of temperature on the product distribution, it is found that CO2 and C2H4 are stable products of thermal decomposition, while some small molecular hydrocarbons such as CH4 and H2 are products at different temperatures. By studying the generation process of these dissolved gases, it is possible to provide a theoretical basis for the research on the DGA method of synthetic ester oil.