Accession Number : ADA325898

Title :   The Effects of the Failure Diameter of an Explosive on Its Response to Shaped-Charge Jet Attack.

Descriptive Note : Final rept. Jul 92-Dec 95,

Corporate Author : ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Personal Author(s) : Lawrence, William ; Starkenberg, John

PDF Url : ADA325898

Report Date : APR 1997

Pagination or Media Count : 42

Abstract : In order to shed some light on the response of explosives to the attack of small-diameter projectiles such as shaped-charge jets, a computational study using the 2DB code and the Forest Fire explosive initiation model for Composition B was conducted. In our computations we modeled the jet as a cylindrical projectile with a flat end that moves without stretching. Jet attack simulations were run in order to determine modes of initiation and critical velocity for initiation as a function of jet diameter. The diameter of the jet was varied between 0.3 and 12.0 The velocity of the jet was varied between 0.8 and 15.0 km/s. The target diameter was at least three times the jet diameter, and the target was between 4 and 60 jet diameters deep. Two modes of initiation associated with shaped-charge jet attack were observed. Prompt impact-mode initiation occurred for both subsonic and supersonic penetration. Delayed penetration-mode initiation occurred only for supersonic penetration. The velocity threshold for large subsonic jets agreed with the Jacobs-Roslund fit. For jets with diameters smaller than the failure diameter of the explosive they attack, higher velocities than predicted by Jacobs-Roslund were required for initiation. A critical boundary between impact- and penetration-mode initiation was determined over the entire supersonic range. A similar boundary between penetration mode initiation and initiation failure for 0.3-mm and 1.5-mm-diameter jets was found, but the initiation failure threshold for other jet diameters has not yet been determined.

Descriptors :   *EXPLOSIVES, *SHAPED CHARGE JETS, VELOCITY, SIMULATION, DIAMETERS, COMPUTATIONS, PROJECTILES, THRESHOLD EFFECTS, ATTACK, TARGETS, BOUNDARIES, PENETRATION, CYLINDRICAL BODIES, SHAPED CHARGES, FAILURE(MECHANICS), SUPERSONIC CHARACTERISTICS.

Subject Categories : Ammunition and Explosives

Distribution Statement : APPROVED FOR PUBLIC RELEASE