Experimental study of the column shape and the roughness effects on the vortex-induced motions of deep-draft semi-submersible platforms

Autor(es)

Goncalves, Rodolfo T. ^{[1, 2]} ; Fujarra, Andre L. C. ^{[2, 3]} ; Rosetti, Guilherme F. ^{[2, 4]} ; Kogishi, Andre M. ^[5] ; Koop, Arjen ^[6]

Afiliação do(s) autor(es)

^[1] Univ Tokyo, Sch Frontier Sci, Dept Ocean Technol Policy & Environm, 5-1-5 Kashiwa No Ha, Kashiwa, Chiba 2778561 - Japan

^[2] Univ Sao Paulo, Escola Politecn, Dept Naval Architecture & Ocean Engn, TPN Numer Offshore Tank Lab, Sao Paulo, SP - Brazil

^[3] Univ Fed Santa Catarina, Dept Mobil Engn, Joinville Campus, Joinville, SC - Brazil

^[4] Argonaut Engn & Res, Sao Paulo, SP - Brazil

^[5] IPT Inst Technol Res State Sao Paulo, Sao Paulo, SP - Brazil

^[6] MARIN Maritime Res Inst Netherlands, Wageningen - Netherlands

• Tipo de documento: Artigo Científico
• Fonte: OCEAN ENGINEERING; v. 149, p. 127-141, FEB 1 2018.
• Citações Web of Science: 4

Resumo

Experiments regarding the VIM of SS platforms with four columns were carried out to investigate the effects of the surface roughness and the column shape. Two different geometry of columns were experimented: rounded-square and circular-cross sections. Each model had the same arrangement of four pontoons in a closed configuration. The range of reduced velocity was from 4 up to 25 covering Reynolds numbers from 7.000 to 80.000. Three angles of incidences for each model were tested, namely 0, 22.5 and 45. For each model, three different levels of roughness were tested. Regarding roughness effects the results seem to confirm two aspects: the important role played by the separation point near the rounded corners of the rounded-square columns and the roughness effect on the boundary layers of the circular columns. Regarding the effect of the column shape, the results indicated that the heading effects on the VIM of SS strongly depend on the column shape. The characteristic motion periods upheld the resonance behavior for the motions in the transverse direction and yaw motions for the lock-in range. Heave, roll and yaw motions did not impact the VIM behavior in the horizontal plane, and their amplitudes were not considered relevant. (AU)

• Processo FAPESP: 14/02043-1 - Comportamento de plataformas de petróleo sob a ação do fenômeno de VIM e incidência simultânea de ondas
• Beneficiário: Rodolfo Trentin Gonçalves
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado