DYNAMIC RESPONSE OF A 120 MM SMOOTHBORE TANK BARREL DURING HORIZONTAL AND INCLINED FIRING POSITIONS

Abstract

IN THIS STUDY, THE DYNAMIC INTERACTION BETWEEN A 120 MM SMOOTH-BORE TANK BARREL MODELED AS AN EULER-BERNOULLI CANTILEVER BEAM AND AN ACCELERATING PROJECTILE DURING FIRING IS PRESENTED. THE INTER-ACTION WAS MODELLED USING A NEW FEM APPROACH THAT TOOK INTO AC-COUNT THE PROJECTILEÂS INERTIA, CORIOLIS, AND CENTRIPETAL FORCES AND THE HORIZONTAL AND INCLINED POSITIONS OF THE BARREL. THE MASS, EXIT VELOCI-TY AND ACCELERATION EFFECTS OF THE PROJECTILE ON THE DYNAMICS OF THE BARREL WERE INVESTIGATED. THE EFFECTS OF THE PROJECTILEÂS INERTIA, AND CORIOLIS AND CENTRIPETAL FORCES WERE EVALUATED AS WELL. FURTHER-MORE, THE TIP DISPLACEMENTS AT DIFFERENT FIRING ANGLES WERE DETER-MINED BY TRANSFERRING THE MASS, STIFFNESS AND DAMPING MATRICES OF THE BARREL WITH THE ADDITION OF THE INSTANTANEOUS PROPERTY MATRICES OF THE PROJECTILE FROM A LOCAL COORDINATE TO THE GLOBAL CARTESIAN COOR-DINATE WITH THE AID OF TRANSFORMATION MATRICES. FINALLY, THE BARREL VIBRATIONS CAUSED BY THE SUCCESSIVE FIRINGS WERE EVALUATED UNDER DIFFERENT FIRING SCENARIOS. TO DEMONSTRATE THE VALIDITY OF THE CURRENT STUDY, COMPARISONS WERE MADE WITH THE RESULTS OF PREVIOUS STUDIES AND A GOOD AGREEMENT WAS ACHIEVED. BY USING THE METHOD RECOM-MENDED IN THIS STUDY, IT IS POSSIBLE TO DETERMINE THE ACCURATE DY-NAMIC BEHAVIOR OF ANY BARREL WITH SUFFICIENT SENSITIVITY, WITHOUT ANY COSTLY OR TIME-CONSUMING TESTS BEING NECESSARY.