Study on Coherence of PTFE/Al Reactive Liner Shaped Charge Jet

The coherence of reactive liner shaped charge jet is related to the combined explosive damage capability of the jet. The conditions and influencing factors for the coherence of reactive jet are studied through theoretical analysis, numerical simulation and experiments. Based on the forming conditions for inert metal jet, cohesion conditions and the PER theory, the coherence conditions of reactive jet and the critical collapse angle curve of the reactive liner are obtained, and the matching mechanism between explosive velocity and liner cone angle is revealed. The influence characteristics of three typical explosives (8701, Comp B and TNT) on the coherence of reactive jet at cone angles of 50° and 60° are obtained from numerical simulation and pulsed X-ray jet formation experiments. The results show that the formed jet has typical incoherence properties due to the lower sound velocity of PTFE/Al reactive material. The critical explosive velocity is positively correlated with the cone angle and due to the lower sound velocity of PTFE/Al reactive material of reactive material. The PTFE/Al reactive jet has the best cohesion at cone angle of 60° when TNT charge is used. The smoothed particle hydrodynamics (SPH) calculation method can be used to well simulate the forming characteristics of reactive jet within the time for jet to reach standoff of 2 charge diameter position.