混杂纤维CNG2气瓶有限元分析及疲劳寿命预测

FINITE ELEMENT ANALYSIS AND FATIGUE LIFE PREDICTION OF HYBRID FIBER CNG2 CYLINDER

推广燃气汽车对于雾霾治理和综合利用清洁能源具有重要意义。在建立碳/玻混杂纤维CNG2气瓶有限元模型的基础上,分析了内胆及纤维层在未经预紧和经过预紧两种情况下的应力差异,通过提取内胆筒体段危险点在载荷历程中的名义应力强度,计算了低周疲劳载荷作用下的局部应力应变,结合Manson-Coffin公式计算得到疲劳寿命。计算结果表明,未经预紧情况下,碳纤维的混入可以使气瓶的疲劳寿命提高7%,同时改善内胆局部应力集中,而经过预紧工艺的混杂纤维气瓶的疲劳寿命则进一步提高19%。

Promoting gas vehicles is of great significance for haze treatment and use of clean energy. On the base of establishing a carbon /glass hybrid fiber CNG2 gas cylinder finite element model,the stress difference about liner and fiber layer under two conditions,without preloading and preloading,is analyzed. By reading the nominal stress intensity of the dangerous point of the liner cylinder during loading history,the local stress and strain under low cyclic fatigue loading are calculated firstly,and then the fatigue life is calculated by combining Manson-Coffin formula. The calculation results show that blending with carbon fiber can increase the fatigue life of cylinders by 7% in the absence of preloading. Meanwhile,the local stress concentration of the liner is improved. The fatigue life of pre-tightened hybrid fiber cylinders is further increased by 19%.