Theoretical Modelling of Shaped Charges in the Last Two Decades (1990-2010): A Review

Shaped charges are used for the penetration of targets in all three dimensions of warfare – land, air and naval. With fillings of high explosives compositions inside, they generate a thin high velocity metal jet, which can perforate the targets. Shaped charges can penetrate tanks with thick armour protection, they can destroy bunkers, they can destroy aircraft and are also useful for attacking ships or submarines. Although shaped charges have a very long history since the Second World War, theoretical modelling efforts started with the steady state theory of Birkhoff in 1948. This theory was modified by the non-steady state theory known as the PER theory of shaped charges. Later, several contributions from experimental evidence were incorporated in the theoretical formulations, and the mathematical models were refined by including the virtual origin, and physical qualities of the jet breakup time, defragmentation into particulates time, the diameter of the metal jet, wave amplitude etc. To review the development of theoretical modelling of shaped charges, three stages are defined. The first is the development until 1990, when the theory of shaped charges was fully developed and penetration predictions with fairly good accuracy were possible. The second stage reviews work carried out in the last decade of the 20th century. During this period good experiments were planned, parametric study was carried out and the results incorporated in the mathematical model of shaped charges. The third stage is all work done in the 21st century (2000-2010), when the tools for advanced diagnostics, new fabrication and inspection, as well as new liner materials were incorporated. The anomalies obtained were resolved by further refinements in the developed theoretical models. The unexplored areas of the theoretical modelling of shaped charges are also enumerated in this paper.