文档介绍：J. Shanghai Jiaotong Univ. (Sci.), 2009, 14(4): 435-442
DOI: -009-0435-2
Simplified Model for Evaluation of VIV-induced Fatigue Damage of
Deepwater Marine Risers
XUE Hong-xiang (薛鸿祥), TANG Wen-yong∗(唐文勇), ZHANG Sheng-kun (张圣坤)
(State Key Laboratory of Ocean Engineering, Shanghai Jiaotong University, Shanghai 200240, China)
Abstract: A simplified empirical model for fatigue analysis of deepwater marine risers due to vortex-induced
vibration (VIV) in non-uniform current is presented. A simplified modal vibration equation is employed according
to the characteristics of deepwater top tensioned risers. The response amplitude of each mode is determined by a
balance between the energy feeding into the riser over the lock-in regions and the energy dissipated by the fluid
damping over the remainder based on the data from self-excited oscillation and forced oscillation experiments of
rigid cylinders. Multi-modal VIV fatigue loading is obtained by the square root of the sum of squares approach.
Compared with previous works, this model can take fully account of the main intrinsic natures of VIV for low
mass ratio structures on lock-in regions, added mass and nonlinear fluid damping. In addition, a closed form
solution of fatigue damage is presented for the case of a riser with uniform mass and cross-section oscillating in
a uniform flow. Fatigue analys