Numerical Simulation of All-Composite Compressed Natural Gas (CNG) Cylinders for Vehicle

Failures of all-composite CNG cylinders for vehicle in service were mainly caused by defects such as crazes, and cracks, etc. in cylinder liners. Authors adopted ANSYS software to conduct numerical simulation of all-composite CNG cylinders, and used a top-down modeling approach to model cylinders, obtaining the cloud diagrams of stress and strain under operating pressure, test pressure and bursting pressure. The main causes of defects were insufficient strength of liner material and unreasonable structure of cylinder. Therefore, designer should select the liner material reasonably and improve the structural design of the transition area from the cylinder body to valve.