Application of High-precision Fibre-optic Strain Sensors to Monitor the Burst Behaviour of Composite Pressure Vessels

Carbon fibre overwrapped pressure vessels (COPV) will account for a large part of the composite market for transportation in the coming years. High storage pressures of hydrogen combined with strict regulations for monitoring the structural condition make sensor integration for COPV viable. The aim of the study presented is to monitor hydraulic (slow-) burst tests with sensors to enable conclusions to be drawn about deformation and failure prediction. Multiple hydraulic burst tests of type-IV pressure vessels with high-definition fibre-optic sensors (HD-FOS) integrated into the laminate, which allow continuous measurement of strain in composite materials, are presented. The forced failure behaviour of a vessel with a designed burst pressure of 900 bar can be recorded by the radial and axial strain change of the laminate. The measured laminate strain shows correlation with the surface strain of the vessels recorded by strain gauges. Additionally, the paper describes the influence of sensor integration on achievable burst pressures and safe failure behaviour. The presented data gives insight into burst behaviour and therefore structural health monitoring (SHM) of COPV. With the help of SHM, COPV can gain market maturity, which would strengthen the case for hydrogen mobility as the means of transport of the future.