Experimental Investigation on Vortex Induced Vibration of Marine Risers with Different Wall Thicknesses

Abstract

In this paper, the vortex-induced vibration experiment of the risers with different wall thicknesses in wave-flow combined water flume was carried out. The dynamic strain sensing technology was adopted. The sensitivity and micro evolution pattern of riser VIV response relative to wall thickness were examined by varying the wall thickness of various riser models, comparing the dimensionless root mean square of strain, vibration frequencies and trajectories by varying different wall thicknesses of the risers. The results indicate that the wall thickness does not have a large influence on the Strouhal numbers of the vibration of the risers, which are always around 0.18; the larger the wall thickness is, the earlier the lock-in region is jumped out, as wall thickness increases, the outflow velocity corresponding to the occurrence of an “8” or oblique “8” shape vibration trajectory continues to delay, and the velocity range for such trajectories gradually narrows.