双剪及古典强度理论应用于火炮身管的强度及振动研究

Application of the Twin Shear and Classical Strength Theory to Strength and Vibration Research of Gun Barrels

火炮进行安全且高精度的射击,需要设计出有合理强度和振动特性的身管。基于内弹道p-l曲线得出的平均压力曲线作为身管壁压载荷建立了某火炮身管有限元模型,通过ANSYS Workbench对身管进行了强度及振动分析。推导了双剪强度理论用于身管弹性强度极限的方法,同时给出了采用平均压力法设计身管时基于不同强度理论需要匹配的安全系数。根据3种古典强度理论以及双剪强度理论对比了身管弹性强度极限随外径内径比的变化,校核了身管结构强度,求解了对应的安全系数。分析结果表明,双剪强度理论用于身管设计是合适的,由此理论设计的身管偏安全,其质量相对我国现行第二强度理论设计的身管增加的最少,设计的火炮身管强度满足使用要求,且避开了激振力的共振频率范围,不会导致结构共振现象的发生,结构设计较为合理,该研究为身管设计提供了一定的参考。

A gun barrel with reasonable strength and vibration characteristics should be designed for the gun to fire safely and accurately.The finite element model of a gun barrel is established based on the average pressure curve obtained from the p-l curve of internal ballistics as the barrel wall pressure load.And the strength and vibration of the gun barrel are analyzed by ANSYS Workbench.The method of applying the twin shear strength theory to the elastic strength limit of the barrel is deduced,and safety factors matching with different strength theories are given when the average pressure method is used to design the barrel.According to three classical strength theories and the twin shear strength theory,elastic strength limit variations of the barrel with the ratio of the outer and inner diameters are compared,the structural strength of barrel is checked,and the corresponding safety factor is solved.Analysis results indicate that the twin shear strength theory used in the design of gun barrels is appropriate,and barrel design based on the theory is safer,its weight increase is minimum compared with the currently used second strength theory.The gun barrel designed based on the twin shear strength theory meets the requirements of use and avoids the resonance frequency range of exciting forces.With structural design optimized,it will not lead to structural resonance phenomena.The research provides some reference for the design of the gun barrel.