This paper reports on the investigation of detonation initiation by shock diffraction on a set of the single detonation.With kinds of different reflector

the pressure histories and flame propagation velocities in the detonator tube were measured to study the characteristics of detonation initiation.The results indicate that the shock diffraction could prompt the initiation of detonation

and which were affected by the dimension of the cone and plate of reflector.With same blockage ratio of the cone

there has a optimal cone angle where the DDT(deflagration to detonation transition) distance was minimum.The DDTdistance would be lengthened when the gap between the cone and plate was increased

but the pressure of detonation wave was influenced little by the reflector.