Comparative analysis of measured and calculated radiation intensities in polymer ablated arcs

Abstract The accurate prediction of radiation intensities in polymer-ablated arcs is crucial for optimizing the design and performance of electrical devices, such as circuit breakers, which rely on polymer ablation for arc control. In this study, both experimental measurements and numerical simulations were conducted to evaluate the radiation intensities of polymer-ablated arcs using a one-side flow outlet model. The experiment focused on light intensity profiles, while the numerical simulations accounted for the distribution of radiation coefficients derived from temperature and mass fraction of vaporized polymers. To accurately capture the arc behavior, the radiation coefficient was calculated considering both molecular and atomic spectra, with particular attention to the C 2 Swan bands and Hα/Hβ atomic lines. The model effectively reproduced the experimentally measured light intensity distributions for different polymers—PA6, POM, and PTFE—despite the complexity of the radiative transfer calculations. Significant variations in radiation intensity between the polymers were attributed to differences in molecular composition and ablation characteristics. This study demonstrates that even a simplified approach to calculating radiation coefficients, using mean absorption coefficients and axisymmetric assumptions, provides results in strong agreement with experimental data. The findings highlight the essential role of molecular spectra in predicting and diagnosing polymer-contaminated arc characteristics, such as plasma temperature and polymer vapor distributions. Comparison between experimental measurements of light intensity and the calculated intensity distributions enables the accurate estimation of number density distributions of each of species in the arc plasmas, significantly advancing the understanding of polymer-vapor contaminated arcs.