Journal of Theoretical and Applied Physics (JTAP) Estimation of photo-degradation of dielectrics surrounding the narrow channel due to PD activity Volume 8 (2014) Issue 4, November and December 2014 2023 11 17 Estimation of photo-degradation of dielectrics surrounding the narrow channel due to PD activity 10.1007/s40094-014-0144-6 EN Journal Article 2023 11 17 AbstractPartial discharge (PD) taking place within narrow channels produces a large number of charged particles, causing degradation of the polymer. Additionally, PD pulses also produce UV photons due to decay of excited states (radiative states) in air. These may have enough energy to break C–C bonds and thereby add to the degradation of the dielectrics surrounding the narrow channel. In this paper, a radiation transport (RT) model has been developed and integrated with a Particle-in-Cell/Monte Carlo collision (PIC-MCC) model to study the behavior of excited (radiative) states of air within discharge in the narrow channel. The radiative state atoms are described by a fluid model combined with the Holstein–Biberman equation. This model has the ablation to follow the spatial evolution of the radiative excited-state density throughout narrow channel. The effect of applied electric field, narrow channel dimensions, gas pressure on the extent of degradation of dielectrics surrounding the narrow channel is studied.