Abstract
Spar platforms could be subject to vortex-induced-motions (VIM) in certain current conditions. Lockin is a phenomenon which occurs in a range of reduced velocities in VIM. In this paper, a new concept of spar platform called cell-truss spar is studied using both computational fluid dynamics (CFD) and model test to investigate the VIM of the spar under different reduced velocities. The unique configuration of the cell-truss spar is carefully considered, and the unsteady flow around the spar is calculated and visualized in CFD simulations. A physical model with a scale ratio of 1:100 of the cell-truss spar is fabricated, and model tests are carried out in the current-generating ocean engineering basin. Many important parameters in VIM of the cell-truss spar are obtained, the occurrence of lock-in phenomenon is successfully simulated, and the mechanism and rules of lock-in are analyzed.
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Foundation item: the National High Technology Research and Development Program (863) of China (No. 2006AA09A107) and the Key Fundamental Research Project of Science and Technology Commission of Shanghai Municipality (No. 07XD14018)
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Wang, Y., Yang, Jm. & Lü, Hn. Computational fluid dynamics and experimental study of lock-in phenomenon in vortex-induced motions of a cell-truss spar. J. Shanghai Jiaotong Univ. (Sci.) 14, 757–762 (2009). https://doi.org/10.1007/s12204-009-0757-0
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DOI: https://doi.org/10.1007/s12204-009-0757-0