Blind predictions of laboratory measurements of vortex-induced vibrations of a tension riser

This paper compares laboratory measurements of the vortex-induced vibrations of a riser in a stepped current with blind predictions obtained with I I different numerical models. Results are included oil in-line and transverse displacements and curvatures, and dominant frequencies. In general, empirical models were more successful at predicting cross-flow displacements and Curvatures than Current codes based oil CFD. Overall ratios between predictions and measurements of cross-now displacements were around 95% and 75%, respectively. Predictions of cross-flow curvatures were more scattered, and almost all were unconservative. In-line vortex-induced curvatures, which may cause as much damage as cross-flow curvatures, could not be computed by any of the empirically based codes, and in general those based oil CFD were in very poor agreement with the measurements. (c) 2005 Elsevier Ltd. All rights reserved.