钢悬链式立管涡激振动疲劳损伤参数分析

Parameters analysis of vortex induced vibration fatigue damage on steel catenary riser

针对钢悬链式立管的结构特性,采用了简化后的振动模型。先对立管进行了模态分析;再根据立管的模态特性结合环境水流参数,采用模态叠加法对立管进行了涡激振动疲劳损伤分析。分析过程中,通过改变流速大小、立管壁厚、立管外径、内部介质以及抑制立管涡激振动的螺旋列板长度等参数,对立管的涡激振动疲劳损伤进行了相应的参数分析。结果表明:立管疲劳损伤随水流速度的增大、立管外径的增大以及内部介质密度的降低呈现上升趋势,但是壁厚变化对立管疲劳损伤大小影响却不显著。

According to the characteristics of steel catenary riser, a simplified model of vibration is estab- lished. Modal analyses of risers are carried out; vortex induced vibration fatigue damages are analyzed based on modal superposition method combined with modal properties and environmental current parameters. Pa- rameters analyses of vortex induced vibration fatigue on steel catenary risers are executed by changing current velocities, risers＇ wall thicknesses, outer diameters, inner fluid densities and strake lengths. The results indicate that fatigue damages of risers increase with current velocity and outer diameter increase and inner fluid density decreases respectively,but the fatigue damages do not change obviously when wall thickness varies.