Fatigue reliability assessment of offshore catenary risers conveying internal slug flow

This paper proposes a fatigue reliability assessment method of offshore steel catenary risers (SCRs) caused by internal slug flow. Offshore risers subject to slug flow are modeled first by employing a finite element method scheme. Subsequently, a combination of Kriging metamodel and Monte Carlo simulation (MCS) is established to assess the fatigue reliability of SCRs conveying internal slug flow. An explanatory example of a 16-inch SCR is presented to validate the performance of the proposed method and the results indicate that the failure rates of the SCR are significantly affected by the frequency of slug flow. Moreover, the accuracy and feasibility of the present method are validated by a comprehensive comparison with the existing experiments and numerical results. The present method contributes to the design and maintenance of offshore risers with internal slug flow.