抄録
Regarding the CO2-O2 mixture gas (20% O2) as the arc quenching gas in a high-voltage circuit
breaker, the predominant component species with high number fractions at temperatures of 300-
20,000 K are determined in consideration of the admixture of the vapor ablated from PTFE (polytetrafluoroethylene) nozzles. In the evaluation, not only 48 gaseous species but also the carbon atom in solid phase (graphite) are taken into account as component species. The evaluation results reveal that C, O, C+, O+, F, F+, CO, COF2 and CO2 in gaseous phase behave as the predominant component species at temperatures above 2,000 K, while not only CO2, O2 and CF4 in gaseous phase but also C in solid phase behaves as the predominant component species at temperatures of 2,000 K or lower. In addition to O2 and CF4 number fractions, the number fraction of C in solid phase also manifests very pronounced dependence on the PTFE vapor concentration. The same evaluations are made for CO2 gas to reveal the effect of O2 addition on the predominant component species, especially on less production of graphite.
