Velocity Compensation in Shaped Charges

Shaped charges (SC) have been used as a means of explosives in military andcivilian use for decades. Thus, there is a substantial amount of research behindthis area. However, as this is a sensitive subject much of this research is notpublicly available. This thesis will look at how one can use asymmetries in SC’s to velocity compensatethe jet formation. Velocity compensation is required when the SC is perpendicularto the projectile direction, hence, leading to an angled jet which decreases thepenetration potential. The asymmetries that were investigated are• off-­center detonation• angled liner• displaced wave shaper• displaced wave shaper & angled liner. The 3D explosive simulation was conducted in IMPETUS AFEA solver and tocompare the performance of these asymmetries the position and velocity of thejet were measured. To create a baseline a simulation without any asymmetrieswas used. The off­-center detonation showed some velocity compensating characteristicsat the tip of the jet. However, as the jet progressed it converged towards thereference. Angled liner simulations were conducted with an angle of 0.5 degrees and 1 degreeand these asymmetries behaved vastly differently. Angled Liner 0.5 degrees hada greater jet angle but a greater quantity of the jet particles were concentratedaround one point increasing the penetration potential. A general characteristicthat angled liner displaced was the fact that it had desirable velocity compensatingtraits all through the jet. Displaced Wave Shaper, like off­-center detonation, showed promising velocitycompensating attributes at the tip of the jet, however, it too converged towardsthe reference on the later part of the jet. When combining the displaced wave shaper and angled liner asymmetries thedesire was to also combine their velocity compensating traits, i.e achievingthe displaced wave shaper’s tip compensation with the angled liner’s totalcompensation. Unfortunately, this was not achieved. The tip, again, showedpromising velocity compensating attributes but the rest of the jet convergedtowards the reference. Conclusively, angled liner shows the highest potential for compensating thevelocity and allowed the most amount of jet particles to be concentrated aroundone point increasing the penetration potential.