Abstract: The current interruption capability of a gas, when used in high voltage gas-blast circuit breakers, depends not only on its material properties but also the flow field since turbulence plays a dominant role in arc cooling during the interruption process. Based on available experimental results, a study of CO₂ switching arcs under a DC (direct current) current in the model circuit breaker has been conducted to calibrate CO₂ arc model and to analyse its electric and thermal property. Through detailed analysis of the results mechanisms responsible for the temperature distribution are identified and the domain energy transportation process of different region discussed. The present work provides significant coefficients for CO₂ switching arc simulation and gives a better understanding of CO₂ arc burning mechanisms.