Experimental investigation of vortex-induced vibration suppression in partially submerged cylindrical hulls using flow-control rods

Autor(es)

Silva, Monica L. L. ; Silva, Paulo H. N. ; Assi, Gustavo R. S.

• Tipo de documento: Artigo Científico
• Fonte: OCEAN ENGINEERING; v. 336, p. 9-pg., 2025-09-01.

Resumo

This study adds and focuses on the limited draft condition to the vortex-induced vibration line of scientific work. A partially submerged circular cylinder was equipped with passive flow-control rods, allowing draft variation. Tests were conducted in a recirculating water channel with a free surface, maintaining subcritical Froude numbers to minimize wave effects. A rigid acrylic cylinder, oscillating only in the cross-flow direction, was fitted with eight rigid rods evenly distributed around its perimeter. Three aspect ratios (L/D = 1.0, 1.5, and 2.0) were tested over Reynolds numbers from 10,000 to 50,000. Results show that control rods consistently reduced vibration amplitudes by over 40%, peaking at 49% for L/D = 1.5, while preserving the fundamental shedding mechanism. The synchronization range was slightly narrowed, and residual vibrations due to turbulence were observed. Mean drag and lift fluctuations also decreased significantly, with drag reductions between 26% and 38%. These results demonstrate the effectiveness of passive flow control for VIV mitigation in finite-length cylinders, offering insights for offshore platform design in the energy transition. (AU)

• Processo FAPESP: 22/03698-8 - OTIC Centro de Inovação em Tecnologia Offshore
• Beneficiário: Gustavo Roque da Silva Assi
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia
• Processo FAPESP: 11/00205-6 - Desenvolvimento de métodos de supressão de vibrações induzidas pelo escoamento em estruturas oceânicas
• Beneficiário: Gustavo Roque da Silva Assi
• Modalidade de apoio: Auxílio à Pesquisa - Regular