关键词: 复合材料气瓶, 缠绕层缺陷, 有限元模拟, 最大应力准则

Abstract: In the process of production and manufacturing, collision and friction would inevitably occur in the large-volume steel liner composite cylinder, which would cause damage on surface of the winding layer and reduce safety of cylinder. Because of the high cost of cylinder, it would cause great economic loss if cylinder with surface defect of winding layer was scrapped. Therefore, it was necessary to conduct finite element analysis on cylinders with winding layer defects. The finite element software was used to construct a large volume hoop-wrapped composite cylinder model, and three volume defects were established on surface of the winding layer. The process of numerical model and defect establishment were described in detail. Stress distribution and size of cylinder liner and winding layer with different winding layer surface defects were analyzed under the design burst pressure (50 MPa), and cylinder burst pressure in each case was predicted by maximum stress criterion. Then, the simulation results were compared with data of cylinder hydraulic burst testing. Critical size of winding layer that has no effect on burst pressure was studied base on the above discussion. Simulation results show that defects of winding layer had little effect on liner stress, but stress of winding layer would increase sharply, and burst pressure would obviously decrease and depth had a greater influence on it. For cylinder discussed in this paper, the critical size was that the area was 200 mm×200 mm and depth was 1 mm.

Key words: composite cylinder, winding layer defect, finite element simulation, maximum stress criterion