Detonation performance of cylinder TNT-RDX explosives wrapped by spiral aluminum tube storing high-pressure active gases

Cylinder TNT-RDX explosives were wrapped by a spiral aluminum tube that stored high-pressure active gases (H₂, O₂, or CO₂) to improve the detonation performance. Their detonation performance was investigated by underwater explosion and air explosion systems. The underwater explosion results show that hydrogen participating in the detonation reaction of explosives mainly improves the peak overpressure, and simultaneous fragmentation and combustion of the spiral aluminum tube mainly contribute to the improvement of energy parameters. In the air explosion, the hydrogen utilizes ambient oxygen to further improve the peak overpressure of composite explosives. The increase amplitude of energy parameters in the air explosion is much lower than that in the underwater explosion due to the air explosion with a higher attenuation speed of shock waves and detonation temperature. The increase amplitude of oxygen to the peak overpressure (6.429%) is less than that of hydrogen to the peak overpressure (8.066%). The energy improvement of oxygen on composite explosives is best due to changing the object that reacts with the aluminum fragments. The average fragment length of aluminum tube calculated by the Grady model and the Goloveshkin model indicates that aluminum fragments formed by the aluminum tube increase the characteristic length of aluminum that can participate in the reaction.