The present research estimates fatigue life of a type-IV CNG composite cylinder of a road automobile that serves as a super-acute part from a safety perspective. This component is subjected to cyclic internal pressure due to filling and emptying the cylinder. To this end, the mechanical and fatigue properties of different materials were determined experimentally. Transient dynamic analysis was performed to obtain the stress tensor as a function of time in the critical zone using Finite Element (FE) simulation. Next, fatigue life of this critical component was assessed utilizing 3D stress components and employing some well-known fatigue failure criteria for composite materials. The FE and tests results were compared. The most important achievement of the research is that the Epaarachchi and Clausen, Fawaz–Ellyin, and Harris and Gathercole criteria ensure the highest precision (15, 17, and 18% error) for fatigue life assessment of this critical component.

本研究从安全角度评估了作为超急性部件的公路汽车 IV 型 CNG 复合材料气瓶的疲劳寿命。该组件因气缸的填充和排空而承受循环内部压力。为此，通过实验确定了不同材料的机械和疲劳性能。使用有限元 (FE) 模拟进行瞬态动态分析，以获得关键区域中随时间变化的应力张量。接下来，利用 3D 应力分量并采用一些众所周知的复合材料疲劳失效标准来评估该关键部件的疲劳寿命。比较了有限元和测试结果。该研究最重要的成果是 Epaarachchi 和 Clausen、Fawaz-Ellyin 以及 Harris 和 Gathercole 标准确保了这一关键部件疲劳寿命评估的最高精度（15%、17% 和 18% 误差）。