CAE-BASED PREDICTION OF PROJECTILE RESIDUAL VELOCITY FOR IMPACT ON SINGLE AND MULTI-LAYERED METALLIC ARMOUR PLATES

Abstract

THE PRESENT PAPER DEALS WITH THE CAE-BASED STUDY OF IMPACT OF JACKETED PROJECTILES ON SINGLE- AND MULTI-LAYERED METAL ARMOUR PLATES USING LS-DYNA. THE VALIDATION OF FINITE ELEMENT MODELLING PROCEDURE IS MAINLY BASED ON THE MESH CONVERGENCE STUDY USING BOTH SHELL AND SOLID ELEMENTS FOR REPRESENTING SINGLE-LAYERED MILD STEEL TARGET PLATES. IT IS SHOWN THAT THE PROPER CHOICE OF MESH DENSITY AND THE STRAIN RATE-DEPENDENT MATERIAL PROPERTIES ARE ESSENTIAL FOR AN ACCURATE PREDICTION OF PROJECTILE RESIDUAL VELOCITY. THE MODELLING REQUIREMENTS ARE INITIALLY ARRIVED AT BY CORRELATING AGAINST TEST RESIDUAL VELOCITIES FOR SINGLE-LAYERED MILD STEEL PLATES OF DIFFERENT DEPTHS AT IMPACT VELOCITIES IN THE RANGE OF APPROXIMATELY 800-870 M/S. THE EFFICACY OF CORRELATION IS ADJUDGED IN TERMS OF A ÂCORRELATION INDEXÂ, DEFINED IN THE PAPER, FOR WHICH VALUES CLOSE TO UNITY ARE DESIRABLE. THE EXPERIENCE GAINED FOR SINGLE-LAYERED PLATES IS NEXT USED IN SIMULATING PROJECTILE IMPACTS ON MULTI-LAYERED MILD STEEL TARGET PLATES AND ONCE AGAIN A HIGH DEGREE OF CORRELATION WITH EXPERIMENTAL RESIDUAL VELOCITIES IS OBSERVED. THE STUDY IS REPEATED FOR SINGLE- AND MULTI-LAYERED ALUMINIUM TARGET PLATES WITH A SIMILAR LEVEL OF SUCCESS IN TEST RESIDUAL VELOCITY PREDICTION. TO THE AUTHORSÂ BEST KNOWLEDGE, THE PRESENT COMPREHENSIVE STUDY SHOWS IN PARTICULAR FOR THE FIRST TIME THAT, WITH A PROPER MODELLING APPROACH, LS-DYNA CAN BE USED WITH A GREAT DEGREE OF CONFIDENCE IN DESIGNING PERFORATION-RESISTANT SINGLE AND MULTI-LAYERED METALLIC ARMOUR PLATES.