高温下における水素の高速燃焼特性

Abstract

The present study of high-speed hydrogen combustion at high-temperatures has been conducted in cooperation with USNRC and was performed at Brookhaven National Laboratory. During a severe accident of light water reactors a large quantity of hydrogen will be generated by the steam-Zircaloy reaction. To evaluate the containment integrity from hydrogen combustion it is necessary to understand the combustion behavior under high temperatures which could occur locally in containment. It should be noted that if a severe accident occurs, the average temperature and pressure in the containment vessel would be maintained below 200°C and 2Pd (Pd: containment design pressure), respectively by the present accident management measures in Japan.Two facilities were used to perform the high-speed hydrogen combustion experiments-Intrinsic detonability experiments were performed to determine a detonation cell size which is used to characterize the mixture's sensitivity to detonation, Also, deflagration to detonation transition experiments were performed to study mixture's sensitivity to detonation through accelerated flame. The experiments were performed at high temperatures and various steam concentrations.Based on these results, the integrity of the containment vessel from detonations has been confirmed because no detonation would happen during severe accident under the present accident management measures in Japan.