摘要
用粘弹性有限元法,分别以尖角形、椭圆形、圆形裂尖反映裂尖的变形,以最大周向应力准则和最大能量释放率准则作为裂纹扩展方向的判断依据,以J积分作为裂纹扩展的起始判据,计算了不同倾斜角裂纹的初始扩展方向。采用多个扩展步递增循环计算的方法,得到了不同倾斜角裂纹的扩展路径,并在扩展路径上设置粘结损伤单元,模拟了裂纹的动态扩展过程。计算结果表明,考虑裂尖构形的影响可更准确地计算出裂纹的初始扩展角度,结合多扩展步循环计算方法和粘结损伤单元,可有效地模拟固体推进剂的断裂过程。
The viscoelastic finite element method was adopted and the effect of crack tip＇s deformation is taken into account by various crack tip shapes： sharp angle,ellipse or circular.Maximum tangential stress criterion and the maximum energy release rate criterion were used to estimate the initial crack propagation angle,and J integral criterion was introduced to estimate the initiation of crack propagation.Propagation paths of different cracks were calculated by multiple expanded steps calculation method.Then the cohesive elements were set along the crack propagation path to simulate the dynamic crack propagation process.Results show that,the initial crack propagation angle can be calculated more accurately,considering the crack tip shape＇s influence.Fracture process of solid propellant can be effectively simulated with multiple expanded step circulation calculation method and cohesive element.
出处
《固体火箭技术》
EI
CAS
CSCD
北大核心
2011年第1期28-31,47,共5页
Journal of Solid Rocket Technology
关键词
固体推进剂
裂纹扩展
粘结损伤
粘弹性
有限元法
solid propellant
crack propagation
cohesive damage
viscoelastic
finite element method
