In this paper, the fracture behavior of a pressure vessel involving a full circumferential wall crack at the inner surface is investigated by applying the axisymmetric model. By using the extended finite element method (X-FEM), the stress intensity factor is calculated and compared for the case of a crack in the Aluminum monolayer cylinder as well as when the composite coating is mounted on its outer surface. Also, the stress intensity factor is obtained for different crack lengths, materials, and fiber orientations in the composite laminate. The materials of composite laminate are Glass-epoxy and Carbon-epoxy. An axisymmetric extended finite element formulation is developed for the pressure vessel, and a MATLAB programming code is implemented to solve the problem. To validation of developed cod, two examples are solved and compared with the available results of 2LFEM and exact solutions. The results obtained from the axisymmetric X-FEM model is in good agreement with the existing results. The results show that the most reduction of SIFs occurred in pressure vessels with the Carbon-epoxy coating with 0° fiber orientation.

在本文中，通过应用轴对称模型研究了在内表面全周壁裂纹的压力容器的断裂行为。通过使用扩展有限元方法（X-FEM），计算并比较了铝单层圆柱体中裂纹情况以及复合涂层安装在其外表面上时的应力强度因子。同样，对于复合层压板中的不同裂纹长度，材料和纤维取向，可以获得应力强度因子。复合层压板的材料是玻璃环氧树脂和碳环氧树脂。为压力容器开发了轴对称扩展有限元公式，并实现了MATLAB编程代码来解决该问题。为了验证已开发的鳕鱼，解决了两个示例，并将它们与2LFEM的可用结果和精确解进行了比较。从轴对称X-FEM模型获得的结果与现有结果非常吻合。结果表明，SIFs的减少最多发生在纤维取向为0°的碳环氧涂层的压力容器中。