Dimensional Analysis Of The Forming Of Grooved MEFP And Research On The Penetration Of Metal Target By The MEFP

In this paper the formation of the grooved MEFP and the damage effect of the metal target plate by the penetration of grooved MEFP were studied by the comprehensive method consist of the orthogonal design method,the dimension analysis method and the numerical simulation.The research results are the foundation for the further design of the grooved MEFP warhead.The main research contents are as follows:Firstly,the forming numerical simulation blue print of the grooved MEFP is designed by using the orthogonal design method and the results of the numerical simulation are studied.The research results are as follows: The kinetic energy of the sub projectile decreases with the increase of the relative depth of the groove and reaches the biggest when the relative depth is 0.0226.When the angle of relative groove angle is 0.1935,0.3871,0.5806,0.7742,the change of the kinetic energy of the sub projectile is not big,and the kinetic energy of the bullet reaches to the maximum at the relative angle of 0.3871.The kinetic energy of the sub projectile increases with the increase of the relative length of the explosive.The kinetic energy of the sub projectile is the maximum when the relative thickness of the liner is 0.0429.The kinetic energy of the sub projectile is increasing with the increase of the relative liner cover and reaches the maximum at 1.2045,then decreases.The change of kinetic energy of the sub projectile with the relative shell thickness is first increased and then decreased,and the maximum value is obtained when the relative shell thickness is 0.05.Secondly,the relationship between the speed and the angle of the groove,the groove depth,the thickness of the cover,the inner diameter of the liner,the length of the charge,the thickness of the shell were studied by using dimension analysis combined with the results of the numerical simulation scheme designed by orthogonal design method.The function relation is achieved..Thirdly,the damage effect of the metal target plate with different thickness by the penetration of grooved MEFP was studied by using ANSYS/LS-DYNA explicit dynamic analysis program.The research results are as follows: when the target plate thickness is 20 mm,30mm,40 mm,50mm,all the sub projectiles can penetrate the metal target.When the target plate thickness is 60 mm,the sub projectile cannot penetrate the metal target plate,leaving only the crater on the target plate.When the target plate thickness is from 20 mm to 50 mm,the perforated area decreases with the increase of the thickness of the target plate,and the perforation area is zero when the target plate thickness is 60 mm.When the target plate thickness is 20 mm to 40 mm,the residual kinetic energy of the sub projectile is sharply decreased,and the residual kinetic energy of the sub projectile is almost zero when the target plate thickness is 50 mm and 60 mm.Fourthly,the damage effect of the metal target plate with different dip angle by the penetration of grooved MEFP was studied by using ANSYS/LS-DYNA explicit dynamic analysis program.The research results are as follows:When the dip angle of the target plate is 10°,20° and 30°,all the three sub projectiles formed by the liner can penetrate the metal target plate,and there is no phenomenon of splashing.When the dip angle of the target plate is 10°,20° and 30°,all the sub projectiles can penetrate the metal target plate,the first sub projectile penetrates the plate without slashing,the after two projectiles slashed.When the dip angle of the target plate is 60°,the first sub projectile slashed.When the dip angle of the target plate is 65° and 70°,the first sub projectile can penetrate the metal target plate but slashed,the after two sub projectiles cannot penetrate the metal target plate,leaving only the crater on the target plate.When the dip angle of the target plate is 75°,all the three sub projectiles cannot penetrate the metal target plate with slashing.