基于MARC的某火炮身管内表面裂纹三维J积分有限元模型

3D J-Integral Finite Element Model of Inner Surface Cracks in a Certain Gun Barrel Based on MARC

火炮发射一定数量炮弹后,身管容易出现裂纹,从而影响射击安全性。通过分析火炮射击过程中身管的受力情况,并利用MARC有限元软件的虚裂纹技术,探讨了某火炮身管内表面裂纹三维J积分有限元模型的建立方法。通过数值计算,得出了身管内表面裂纹J积分值随裂纹长度及深度的变化规律。根据某火炮身管裂纹扩展的临界J积分值,求出了其在最大膛压作用下临界裂纹尺寸,这对火炮身管的安全性评估及预测具有较大的工程应用价值。

Launching a certain amount of ammunition,it is easy to produce crack in the gun barrel and that will have effect on the security of fire.Through analysis of the gun barrel＇s stress situation in process of gun fire,and by use of virtual crack technology of MARC FEM software,the foundation method of 3D J-integral finite element model of the inner surface cracks on a certain gun barrel was discussed in detail.By means of numerical calculation,the rules of J-Integral values varied with the length and depth of the inner surface crack of gun barrel were obtained.According to the critical values of J-integral,the critical size of the crack was calculated under the condition of maximum chamber pressure.This method has greater engineering application values for security evaluation and prediction of the gun barrel.