Abstract：A series of singleshot detonation experiments of C2H2/air mixtures were performed to investigate the wave and flame acceleration mechanism of DDT
in smooth and obstructed square tube with 60 mm×60 mm×2 000 mm. The ionprobes and the pressure transducers were respectively utilized to get the flame and wave signals. The acceleration mechanism was analyzed according to the position and velocity characteristics of wave and flame in different time along the tube. The results indicate that the flame acceleration plays dominant role in smooth and obstructed tube. The speed of peak value wave is bigger than that of initialized wave and flame. In obstructed tube, the initialized peak value wave and flame simultaneously develop before overdriven detonation. After
overdriven detonation， the speed of initialized wave is temporarily promoted, and the three parts ultimately couple into stable detonation wave.
2017, Vol. 38 
