This paper presents a numerical study regarding the behavior of a tank, when an inner explosion occur. This explosion could be the result of any high energy material type. The initiation point of an explosion is very important, especially in the case of an inner explosion, because from such a point the shock waves begin their moving. In this paper the influence of the initiation point position is researched, using one of the most used way by finite element method. The finite element method is applied using special material model, one of the most used equation of state and a methodology which is implemented in some professional programs.