Design and finite element analysis of metal-elastomer lined composite over wrapped spherical pressure vessel

Over the years, Composite Overwrapped Pressure Vessels (COPV) have been utilized in the aerospace and automotive industries. In the present work, a novel approach has been adopted in designing the liner and test the feasibility of adopted manufacturing and joining techniques. The selection of winding angle and thickness distribution of composite along the meridional direction of the pressure vessel is derived by using an analytical approach based on classical laminate theory. Further, Finite Element Modelling (FEM) software ABAQUS-6.14 is utilized and tested for minimum burst pressure load to account the effects of composite winding angle layup and effective thickness of liner and composite at the pole, dome and equator regions of COPV. Among the various failure criterion of COPV, liner buckling and bond failure between the liner and composite overwrap resulting in the creation of the debond region are considered. These failures are concerned with contact issues and can be minimised by proposing to include a hyperelastic elastomer layer between the liner and composite overwrap. The analytical and FE analysis approach towards predicting the strength response of composite under applied load showed good agreement. At minimum burst pressure load findings showed that overall behaviour, stress-strain distributions and effect of elastomer thickness on liner were found satisfactory. A critical study involving Finite Element Analysis (FEA) based liner alone burst pressure test, and credibility of joining techniques employed in assembly of liner is analysed and found acceptable.