The influence of back-breakdown on the CO2 conversion in gliding arc plasma: based on experiments of different materials and improved structures

Abstract

In this work, we studied the influence of electrode materials and airflow area on CO2 conversion in gliding arc plasma. Herein, the correlation between breakdown events, including back-breakdown and re-ignition, and conversion rate was discussed. The experimental results show that the motion characteristics of the gliding arc when using different electrode materials affect the CO2 conversion, especially the energy efficiency. Thereinto, the graphite material has the best performance. The correlation coefficient between breakdown events and the conversion rate reaches 0.85 at 4 l min−1. Furthermore, the experiment of changing the airflow area verifies this value. Changing the airflow area increases the proportion of gas passing through the gliding arc, which can improve the CO2 conversion, especially at low flow rate. When the flow rate is 3 l min−1, the conversion rate reaches 11.1%, which is much higher than the conversion rate before improvement.