High-speed Flight Dynamic Characteristics Of Discrete Rod And Target Penetration Effect

This paper studies the penetration of discrete rod with high-speed, explore its airresistance and elasticity effect, then select a reasonable damage model and calculationmethods, conducts the simulation research to the discrete rod penetration on typicalmetal target by the nonlinear finite element analysis software LS-DYNA.Using the aerodynamics knowledge, obtains each aerodynamical coefficientexpression of the rod, and using the isoentropic principle, the accidental layer theoryas well as the plane supersonic speed circumferential flow and so on, obtained themiddle coefficient expression, then get air resistance and the moment of resistance,thus lay the aerodynamics foundation for the research of aerial flight condition of thediscrete rod at high-speed.Research on elastic deformation of discrete rod by using vibration theory pointsout, Elastic deformation would change the air resistance of the rod, and have animpact on the rod's movement; then take 45 degrees for example, quantitativelyanalyze the rod elastic deformation on the movement. The results show that the elasticdeformation of the rod have small impaction on Movement, when the problemconcerning on the penetration, we can ignore the elastic deformation, analyze themovement with the rigid body knowledge.The penetration simulation of discrete rod shows that the rod from differentangles could penetrate the target, having different degrees of damage, the penetrationprocess shows complex plastic stress wave propagation, it leads to irregulardestruction surface and the complex broken situation of the rod. Researching ondifferent Penetration parameter, we can see that the material properties and airresistance has little effect to the penetration, but initial velocity, target thickness andthe angle of penetration has clear effects to the penetration. And the effects of damagerequires consideration of the remaining energy of the rod, the weight loss of the target,the area of broken surface and the area of plastic deformation and so on.