火炮固有频率及关键零部件发射应力有限元分析

【作者】 刘军；

【导师】 苟文选；

【作者基本信息】 西北工业大学 ， 工程力学， 2005， 硕士

【摘要】 本文分别分析了火炮的固有频率和火炮在发射过程中关键零部件的发射应力。其中,火炮的固有频率分析采用ABAQUS有限元计算软件的隐式积分模块。关键零部件的发射应力分析采用ABAQUS有限元计算软件的显式积分模块。研究工作的重点是对火炮关键零部件所构成的装配体有限元计算工作提出了适合工程设计应用的有限元计算模型。 针对火炮的固有频率分析,论文主要讨论了制退器的简化方法对计算结果的影响并建立火炮固有频率分析的最佳有限元计算模型;分析了身管材料在不同密度和温度下对火炮固有频率的影响。 针对火炮关键零部件的发射应力分析,论文分别讨论了有限元计算模型的网格疏密程度、对称性模型和接触面简化等因素对计算结果的影响。通过对于各个计算模型的综合分析和比较,建立火炮关键零部件发射应力分析的最佳有限元计算模型。 本文采用的火炮关键零部件的有限元计算模型,是以整个装配体为研究对象,并且采用了步长极小的显示积分法,因此其计算结果更符合真实情况。模拟得到的后坐位移与实验测定值基本符合,计算结果说明火炮发射应力计算模型是可行和有效的。 计算结果表明,各关键部件的发射动应力均小于炮钢材料的屈服极限。对于火炮的各个关键零部件,膛内过程是火炮发射的危险阶段。 有限元计算模型的建立,对于火炮结构优化设计、缩短研制周期和降低火炮设计人员的劳动强度都具有重要意义。本文对于承受爆炸、冲击等瞬态载荷作用下的结构动应力计算也有参考价值。更多还原

【Abstract】 This paper mainly analyzed the natural frequency of a gun and the emission stress in the key parts of a gun when it is in lunch process. The paper used ABAQUS/standard module to simulate the natural frequency of a gun; used ABAQUS/explicit module to simulate lunch process. The paper focused on the establishment of a FEM model which is suitable for engineering application to calculate emission stress in the key parts of the gun on assembly level.To analyze gun’s natural frequency, the paper calculated and discussed the different simplifying methods of muzzle brake on how to affect the computed value of the model and get the best model for this analysis. Further more, the paper analyzed the material of tube in different density and temperature on how to affect the natural frequency of a gun.To analyze the emission stress, the paper discussed the effect of different density of mesh, symmetry, and simplifying to the interfaces. After comparing the results of different models, the best model for this analysis was built in the paper.The analysis is on the assembly level instead of on the basis of single part in the traditional analysis. The increments are very small by using explicit method, so the result is more rational. The recoiling displacement from the numerical simulation showed good agreement with it from simulation tests. So using the model to analyze emission stress of the gun is feasible and effective.The result of simulation indicated that the maximum of Mises stress in all the key parts is less than the yield stress of the gun steel. For all the key parts, the interior ballistic process is dangerous stage in the lunch process of the gun.To the designers of the gun, the building of FEM model is very useful in structural optimization design by shortening the period of design and reducing work intension. This method has reference values in analyzing the dynamic stress in some structures under transient loads such as blast and impact.更多还原