Oil well perforators (OWP) are explosive devices that are used in drilling industries of oil and gas wells to access the reservoir and increase the wells efficiency. Oil well perforators performance is measured by the depth of penetration that can cause, for this reason depth as the main parameter must be examined. In this article, a complete report of numerical simulation and performance optimization of these devices, which are indeed small sizes shaped charges, is presented. To do this, the multi-material eulerian and the lagrangian methods are used for simulation of the jet formation and its penetration into underground rock processes, respectively. For solving the problem of large deformation elements in lagrangian method, erosion criterion elements were used. Because the results of jet formation and penetration Process heavily influenced by the density of the mesh, In this study mesh sensitivity were examined.. Described simulation, is validated by the use of reliable results of some references and then, a new charge geometry is suggested which resolves the inhomogeneities in the distribution velocity of the tail and increases the effective length of jet in the penetration process.