Experimental and Numerical Study of Wake Interference and Clashing Between Steel Catenary Risers

The aim of this work is to estimate the risk of clashing between steel catenary risers (SCRs) due to wake interference. More generally, the validity of clearance analysis between risers as recommended by design codes is discussed. Considering the complexity of the problem, theoretical, numerical and experimental approaches have been used jointly. Similitude rules have been investigated to reproduce Wake Induced Oscillations (WIO) at model scale. Different regimes have been identified (stable, unstable and critical) depending on the intensity and effects of WIO. The validity of steady wake models used in the industry is discussed in view of the experimental data. Finally, onset criteria for WIO and clashing are proposed based on comparison between experimental and numerical results.