Relation of fragment with air shock wave intensity for explosion in a shell

A new analytical method is suggested for the computation of primary fragment velocity for an explosion in a shell (or case). The influence of the shell on the intensity of explosion-generated air shock waves is discussed, which shows that it is determined by the wall thickness (or the mass) of the location at which the fragment occurs, not by the total mass of the shell. By experimentation the air shock wave overpressures and the damage effects of simulative targets that are caused by the explosions of explosive charges in a shell and without a shell are examined under the same charge mass and shape, to verify the validity of the presented result in this work. By using the suggested theoretical method, the upper bound of fragment velocity and the lower bound, respectively, are calculated. The fragment velocity depends on the thickness of a shell, and the thicker or the heavier the shell, the more serious the influence of the shell on blast shock wave intensity.