Numerical analysis on dynamic behaviour of novel grooved cylindrical casing with different explosive loads

The grooved casing has been widely used to control the size of the fragment. In order to study the dynamic behaviour and fragmentation of the novel grooved structure casing with different explosive loads, we established a numerical model in which two kinds of grooves with different depths are alternated on the casing, and different diameter charges are used to form different explosive loading. Through the orthogonal test, the rules of casing fragmentation influenced by different factors are also obtained. The study shows that the novel grooved casing can be ruptured in two fragmentation characteristics with different fragment sizes under different explosive loads. The cylindrical casing first ruptured at Groove I and then the stress in the casing was unloaded, so that the growth of the crack at Groove II was impeded. And there were two strain bands formed from the root of the grooves, and the direction was 45° with the radius. The primary factor affecting the fragmentation of casing is the depth of Groove II, followed by the depth of Groove I and load strength under the conditions studied in this paper.