Diameter Effect on the Propagation of Curved Detonation Waves in Micro-Channel Charges Within a Strong Confinement

The property of detonation wave propagation in micro-channel charges is one of the most important research areas in the field of explosives. Based on DSD (Detonation Shock Dynamics) theory and a linear assumption for the streamline deflection angle, this paper proposes a theoretical model for curved detonation wave propagation in cylinder-type micro-channel charges within a strong confinement of metal tube. Further, dynamic control equations related to the detonation velocity and charge diameter are deduced, a numerical calculation method of detonation velocity and shock front shape is given, and propagation rules for detonation waves with different diameters are obtained. An experiment was designed to test the detonation velocities for micro-channel charges with a booster explosive. The results closely agree with calculations, validating the propagation model of curved detonation waves. It was found that the detonation velocity loss and shock front curvature in the central axis decreased with increasing diameter in the calculation range. Moreover, the smaller the diameter, the greater the rate of change. It is also shown that the model is suitable for the prediction of diameter effects in micro-channel charges, which is of significance for structural design and performance optimization in MEMS initiation systems.