Estimation of static burst pressure in unflawed high pressure cylinders using nonlinear FEA

A study has been carried out to predict the static burst pressure in closed thick-walled unflawed cylinders using finite element analysis (FEA). The failure of the cylinder purely by ductile fracture mode is considered in the analysis. Thick-walled cylinders of different diameter ratios (K=outer diameter/inner diameter, ranging from 1.5 to 6) have been investigated. The commercially available ANSYS FEA code has been used, for carrying out an implicit elasto-plastic analysis of the cylinders considering the geometric and material nonlinearities. The Arc-length algorithm available in ANSYS code has been employed to overcome the solution convergence problem, due to tangent singularity at limit state. The FEA predicted static burst pressure for thick-walled cylinders over the considered range of diameters ratios i.e., K=1.5 to 6, showed good agreement with Svensson burst model. The implication of using elastic-perfectly plastic model for the prediction of static burst pressure has also been investigated.