Abstract: For the dispute between two usually used models (i.e. axisymmetric model and three-dimensional shell element model) in numerical simulation of CNG-2 cylinders,the results between two models was compared in detailed, and the effect caused by filament winding angle was discussed. The conclusion is that: for CNG-2 cylinders,when winding angle of the fiber layer was close to 90°, the stress distributions of two models are basically the same;the theoretical defects of shell element was the primary reason for the radial stress in fiber layer closed to zero when three-dimensional shell element model was used;when winding angle is equal to 90°, three-dimensional shell element model could be replaced by axisymmetric model when the stress analysis of CNG-2 cylinders stress was made, which can reduce computational workload;when the filament winding angle is not equal to 90°, the error between two models changed with winding angle, but is less than 5% when the angle ranged from 90° to 70°, and axisymmetric model can also be used within the engineering permissible range. Those conclusions can provide beneficial guidance for hoop-wrapped composite cylinders numerical analysis.

Key words: CNG-2 cylinder, stress analysis, shell element, axisymmetric, winding angle