The Effect of Ozone Addition on DDT for Ethylene-Oxygen Mixtures in Macro-Scale Tube

Deflagration-to-detonation transition (DDT) is one of considerably important topics in combustion and explosion science. After decades of experimental and numerical studies, the physical process of DDT by which a subsonic deflagration transforms into a supersonic detonation in distinct types of tube has received intense studies[1-3]. It is very important for a better understanding of DDT process and the full development of its potential applications. A large number of works have investigated on DDTs in microand macro-scale channels, demonstrating that micro DDT depends on elongation of flame surface caused by diffusion[4], while turbulent combustion is more dominant for the occurrence of DDT in macro channel. Recently, Ju et al. [5] found that adding ozone in acetylene-oxygen system can promote significantly the appearance of DDT in micro-channel, showing that chemical kinetic effect is dominant for micro-scale DDT compared with thermal and viscous transportation. Wang et al. [6] studied the effect of ozone addition on cellular detonation for hydrogenoxygen mixture, and found that cell size was influenced significantly by chemistry reactions caused from the ozone addition. Consequently, the run-up distance of DDT and the cell size of detonation are closely related to ozone kinetics. However, the study of DDT in macro-scale channel is few considering ozone addition and the kinetic effect of ozone addition in DDT with turbulent-combustion acceleration still needs to be identified. This study aims to examine the effect of ozone addition on DDT in macro-scale tube through experiments.