Research On The Technology Of Tank Crest And Its Time Fuze

The warhead time fuze fitted to multifunctional improved conventional munition of the tank gun requires to throw submunitions accurately over the target. At the same time, it can’t effect during peneteating and the submunitions are detonated by base fuze in vivo to form high-speed fragments that can effectively destroy the target.In order to refer to the analysis of the ballistic condition of fuze, the multifunctional improved conventional munition was simulated and fitted by FLUENT and MATLAB at different Mach, different attack angle and different atmosphere condition. Then the aerodynamic characteristic parameters were got. The average shape coefficient simulated is 1.584. The quadratic function can be used to describe the drag coefficient Cx of projectile varies with attack angle, then attack angle coefficient is got, which is 13.0-16.8. In subsonic and transonic region, the cubic function is more suitable to describe the lift coefficient Cy and the pitching moment coefficient Cmz of the projectile vary with attack angle. In supersonic region, the one function and the cubic function are both appropriate. The drag coefficient Cx increases as the height of the atmosphere increases. The drag Rx and the pitot temperature decreases as the height of the atmosphere increases.In order to refer to the shape design optimization of the warhead time fuze, the influence of three kinds of the warhead time fuzes with improved conventional munition on aerodynamic characteristic was analyzed by FLUENT. The exterior ballistic mathematical model of projectile was established and the influence of three kinds of the warhead time fuzes with improved conventional munition on exterior ballistic was analyzed by MATLAB. Then the aerodynamic characteristic parameters and the exterior ballistic data with different departure angle were received. Three kinds of the warhead time fuzes with improved conventional munition have certain influence on aerodynamic characteristic and exterior ballistic, but the influence is not large. The influence of truncated warhead fuze with improved conventional munition is minimum.In order to analyze the influence of coating on fuze springs’resistance, the mathematic model between fuze springs’resistance and coating based on the elastic-plastic theory were established and the curves of fuze springs’ resistance and coating were received by the finite element method. Also resistance of three kind of springs were measured before and after the plating. The coating has great influence on fuze springs’resistance, which should be paid attention especially to spring design in order to prevent the influence on arming correctly and other performance. The spring resistance increases by 10% after tin plating while the spring is small. Thickness of coating is the main factor on the fuze springs’resistance for the same kind of material and yield strength of coating material is the main factor on the fuze springs’ resistance for different kind of coating materials. For the same coating material and thickness of springs, different diameters of springs have different resistance change rate. The resistance change rate decreases as diameters of springs increase.In order to study the influence of the shape of warhead fuze on the performance, strength and the safety of ejection powder of the projectile penetrating the target of concrete.Concrete penetration with improved conventional munition was simulated by ANSYS/LS-DYNA. Then the results of residual velocity, residual kinetic energy, the extent of damage of the projectile and the maximum stress and strain of ejection powder were received. The truncated warhead fuze has the best penetration effect. In order to ensure the safety of ejection powder, the warhead fuze should use steel material and the thickness of the projectile should be increased. The safety of ejection powder decreases as the speed of the projectile increases. Large angle is very bad to ejection powder.