Cellular Pattern Evolution of Deflagration-to-Detonation Transition in Square Detonation Tube
This paper presents recent results of an experimental investigation on Deflagration to Detonation Transition (DDT) with H2/air and C2H2/air mixtures in 60mm×60mm square detonation tube. The entire process of DDT is demonstrated by cellular patterns and the analysis is mainly based on their evolution.The pressure transducers and ion-probes were utilized to get the pressure and flame history in the tube respectively, and the corresponding cellular patterns are recorded on soot foils along cover board with 60mm×1380mm.Results show that overdriven detonation appears only once and several blast appear in DDT.Cellular patterns show that several twistable lines appear at the obstacle exit neighborhood area , while regular cell takes place after the final twistable line.Details of the cellular pattern indicate that from the early stage to the end of regular cell, the detonation wave sequentially experiences impactive area, abundant secondary cells, secondary cells expanding, local explosive, fine secondary cells, regular cell.
P. G. Zhang et al., "Cellular Pattern Evolution of Deflagration-to-Detonation Transition in Square Detonation Tube", Applied Mechanics and Materials, Vols. 130-134, pp. 3351-3355, 2012