表面损伤对全复合材料车用天然气气瓶强度的影响

STRENGTH INFLUENCES BY SURFACE DAMAGE ON COMPOSITE MATERIALS USED FOR GAS CYLINDERS ON VEHICLES

针对车用全复合材料天然气气瓶在使用中存在的一些表面损伤,利用有限元软件进行了表面损伤对全复合材料气瓶强度影响的研究。在某型全复合材料气瓶的几何构成及制造工艺的基础上,建立了分析的有限元模型。通过统计和分析表面存在的一些损伤,设计了相关的表面损伤类型以及尺寸,并进行了气瓶的强度分析。结果表明:①由于表面损伤的存在,使损伤处不能承受载荷,而与表面损伤相邻的内层纤维受力明显增加;②对于相同尺度的表面损伤,轴向表面损伤对气瓶应力的影响比周向表面损伤显著;③筒身上的损伤相对于其他部位表面损伤要安全。分析结果可为气瓶的强度设计以及检验提供有效的评价指标和方法。

Aiming at surface damages on in-service automobile-used gas cylinders made by composite materials,this study applied finite element software to research on how surface damages had impact on the composite materials.Based on the geometrical configuration and manufacturing process of a certain type of composite gas cylinder,this study set up a numerical model.Through analysis on the strength of this gas cylinder influenced by different kinds and areas of surface damages,this study concluded that firstly the damage point could never endure much more load like before and the bordering fiber parts had to load-bear much higher pressure;secondly the vertical surface damage was more serious than the radial one with the same area;and finally damages on the cylinder body were not as serious as those on the other parts.These study results would be taken as references for either strength design or testing & certification of gas cylinders.