Energy Output Efficiency of Shielded Mild Detonation Cord in Cylinder Structures

Abstract

Abstract Expanding tube separation device is a commonly used linear separation device, whose energy resource is a shielded mild detonation cord (SMDC). In this research, the SMDC is a mild detonation cord sheathed in flat polyethylene. Two experiments were achieved to discuss the energy output efficiency of the SMDC. In the first experiment, the SMDC was inserted into 1060 aluminum cylinder directly. While in the other experiment, the SMDC was insert into aluminum cylinder after contained within a flat steel tube. The velocity and displacement of the characteristic points on the outer surface of the aluminum cylinder during explosion were measured by photonic Doppler velocimetry (PDV). The simulation results with Ls-dyna fluid-solid coupling algorithm correspond well with the experimental results. According to the simulation analysis, the distribution of total energy of explosives were obtained. The plastic strain energy of the aluminum cylinder corresponds to the ability of the SMDC to do external work. The result shows that, 39.3% of the total energy in the explosive is output to aluminum cylinder with SMDC acting on it directly, while the energy output efficiency turns to 20.8% after passing through the flat tube.