Experimental and numerical investigation of viscous effects on parametric roll motion

Çopuroğlu H. İ., Peşman E., Katayama T.

International Ship Stability Workshop, 11-13 September 2023, Istanbul, İstanbul, Türkiye, 11 - 13 Eylül 2023, ss.1-7

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Basıldığı Şehir: İstanbul
  • Basıldığı Ülke: Türkiye
  • Sayfa Sayıları: ss.1-7
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

The chaotic behavior of parametric roll motion is widely known. Briefly, disregarding viscous effects may

have an impact on roll amplitudes, particularly around the velocities where bifurcation takes place. In the

presented study, experimental, numerical, and analytical analyses are used to examine how the behavior of the

ship is altered when viscous effects in parametric roll motion are neglected. In order to compare it with the

approximate analytical solution of the 1 DOF nonlinear equation of parametric roll motion, 6 DOF experiments

are conducted with constant velocities. While there are viscous effects in the experiments, viscous effects are

neglected in the analytical solution since the GZ curves used in the analytical solution are obtained by

hydrostatic methods and does not contain viscous effects. Then, various CFD analyses are carried out to

determine updated GZ curves, which include viscous effects. So, the updated GZ curves that are obtained from

CFD analyses are adapted to the analytical solution, and the results are compared with over the viscous effects.