水分侵入高温硫化硅橡胶扩散行为的仿真研究(一):数值建模与计算OACSTPCD

Water ingress impacts the long-term reliability of silicone rubber composite insulators.With limitations of experiment methods and characterization techniques,however,it is difficult to detect the dynamic diffusion behavior of water ingress into silicone rubbers.Hence,we propose a numerical modeling method to visually simulate the diffusion behaviors of liquid water and water vapor permeating the high temperature vulcanized silicone rubbers,which have been studied in two-part article.This paper focuses on methods of the numerical modeling and calculating,using finite-difference time domain method and Newton-Raphson algorithm,based on the Langmuir diffusion model.It has been programmed by using MATLAB to simulate the dynamic diffusion behaviors of liquid water ingress into silicone rubbers,achieving the spatial distributions of moisture concentration of the specimen section along height and thickness varying with testing time.Two different water phases in mobile and bound states due to moisture absorption have been decoupled from the total moisture content in simulations,and thus their evolving patterns of spatial and temporal distributions can be calculated with the total moisture weight over time.The numerical modeling and calculations have been verified by data error analysis between simulations and experiments.The influences of temperature and the amount of the alumina hydroxide content on the distributions of moisture diffusion behaviors are also studied,whose features are clarified in the Langmuir diffusion curves.The proposed method offers a new thought to study the water diffusion behavior in the silicone rubbers.