Finite element simulation of LDPE/SiO2 nanocomposite

A three-dimensional three-phase model intended to describe the current behaviors of LDPE/SiO₂ nanocomposite under DC voltage is presented. The polarization current and depolarization current are simulated by finite element method based on this model. In order to verify the feasibility of this model, practical currents in LDPE/SiO₂ nanocomposites filled with different content of nano silica are measured, respectively. It is shown that the trends of simulated currents and practical currents are the similar, especially under low doping concentration (below 1%wt in this article). However, the current decay rate of simulated results and experimental results has a little difference, especially under high doping concentration (above 2%wt in this article). Thus, this three-phase model is useful in calculating the current behavior of nanocomposite, although it is not perfect and still needs to be improved.