混合燃料液滴の燃焼における微小爆発の発生について : 第 2 報微小爆発の発生時期に及ぼす初期液滴直径の影響(熱工学, 内燃機関, 動力など)

抄録

The microexplosion occurrence in droplet combustion of miscible binary-fuel droplets has been studied experimentally and theoretically. In experiments, the burning droplet was injected upward, and the induction time for microexplosion occurrence was obtained. Results show that microexplosion induction time is distributed over the quasi-steady vaporization period. The maximum frequency of microexplosion induction time and the occurrence probability of microexplosion increase with the initial droplet diameter. The microexplosion occurrence was modeled considering homogeneous bubble nucleation rate. The present stochastic model well demonstrated the experimental results. The theory shows that these stochastic characteristics of microexplosion occurrence depend on the fifth power of the initial droplet diameter. The bubble nucleation leading to microexplosion depends on the time scale and the superheated liquid volume. The time scale in droplet combustion is proportional to the second power of the initial droplet diameter, and the volume of superheated liquid is proportional to the third power of the initial droplet diameter.