ALE Simulation Of Ultra-high Speed Metal Jet Penetration Into High Strength Concrete Target

As the drilling depth continues to increase,the rock compaction,strength and formation pressure of the reservoir have also increased.In addition to the long drilling time and the thickening of the pollution zone,ordinary perforating bombs cannot meet the requirements of perforation penetration.Only strong perforating bullets can penetrate the thick,high-strength pollution zone.In this paper,using LS-DYNA software,combined with ALE algorithm,considering the confining pressure and the spacing of the high hole density,single and two HS45-5 perforating bullets-gun-liquid-casing-high-strength concrete target three-dimensional finite element model is established to simulate ultra-high speed The formation of the metal jet and the process of penetrating the concrete target.Find out super-fast metal jet energy transformation and energy dissipation in the process of penetration,medicine cover type pressure change rule,jet velocity variation,the confining pressure of jet penetration concrete target speed and the influence law of penetration,to explore the different elastic spacing between playing under the interference of jet energy conversion,the influence law of jet velocity and penetration,Based on this,the penetration mechanism of super-strong projectile penetration into super-strong target with high confining pressure is expounded.The results show that the axial velocity and radial velocity of jet termination penetration under 30 MPa confining pressure are increased by 14.2%,17.1%,and the jet penetration depth is decreased by 11.4% compared with that under no confining pressure.Under 50 MPa confining pressure,the axial velocity of jet termination penetration increases by 33.0%,the radial velocity increases by 42.9%,and the jet penetration depth decreases by 20% compared with that under no confining pressure.The projectile spacing is reduced by 1.5mm,the jet energy conversion rate of the second projectile is reduced by 0.3%,the axial velocity is reduced by 40m/s,the radial velocity is increased by 21m/s,and the penetration depth is reduced by 0.8%;the projectile spacing is reduced by 3mm,and the second projectile The energy conversion rate of the ejection stream is reduced by 2.2%,the axial velocity is reduced by 137m/s,the radial velocity is increased by 123m/s,and the penetration depth is reduced by 7.8%.The research shows that with the increase of reservoir confining pressure,the jet penetration velocity increases and the penetration depth decreases.With the decrease of projectile spacing,the interprojectile interference increases,and the interprojectile interference affects the jet energy conversion rate of the perforating projectile adjacent to the projectile,increasing the radial velocity and decreasing the axial velocity,thus reducing the penetration depth.Through the research in this paper,the penetration mechanism of super-strong projectile penetration into super-strong targets with high confining pressure is clarified,which can provide a basis for the accurate analysis of super-strong projectile penetration penetration and optimization of perforation parameters such as hole density.