Stress Intensity Factor and Shape Coefficient Correction of Non-Penetrating Three-Dimensional Crack for Brittle Ampoule Bottle with V-Shaped Notch

Applied Sciences

Shengji Li¹  Peng Yu²  Xuefeng Huang²  Youping Gong³ 

[1] College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China;Institute of Energy, Department of Physics, Hangzhou Dianzi University, Hangzhou 310018, China;School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou 310018, China;

关键词: stress intensity factor;    shape coefficient;    non-penetrating crack;    finite element method;    ampoule bottle;    sterility inspection;   

DOI  :  10.3390/app12105246

来源: DOAJ

【 摘 要 】

The automatic opening of an ampoule bottle is key to making the operation of the sterility inspection automatic. During the automatic opening, the fracture characteristics on the neck of ampoule bottle need to be deeply understood to avoid the contamination of the samples by preventing the glass fragments from dropping into the ampoule bottle. This paper presents the calculation of fracture characteristic parameters, such as the coefficient K of the stress intensity factor (SIF) and the coefficient F of shape factor (shape coefficient), based on the finite element method (FEM) for a non-penetrating three-dimensional crack. Mechanical and mesh models were built for the special structure of an ampoule bottle with a V-shaped notch, and the influence of mesh size on the coefficient K was evaluated. The mathematical expressions of stress intensity factor and shape coefficient of three types of cracks were established. The results demonstrate that the crack ellipticity (a/c) and crack relative depth (a/t) have significant effects on the K_I, K_II, and K_III of the SIFs. The K_I plays a dominant role, which follows a symmetrical distribution at the symmetrical position on both sides of the deepest crack point, whereas the K_II and K_III can be negligible. The corrected shape coefficient F_I decreases with increasing ellipticity a/c and increases with increasing relative depth a/t under the combined tensile stress and bending loads. The comparison to the literature shows the calculation of the corrected shape coefficient has a high accuracy based on the FEM, which will be applicable and reliable for non-penetrating three-dimensional cracks.

【 授权许可】

Unknown