考虑流固耦合时的海底管道悬跨段非线性动力分析

Nonlinear Dynamic Analysis of Submarine Pipelines Considering Fluid-Structure Interaction

通过对管道的涡激振动试验,提出了考虑流固耦合的非线性涡激升力表达式,并用该式进行了海底管线悬跨段非线性动力响应时程分析。对考虑流固耦合与未考虑流固耦合情况下得到的管道动力响应时程进行对比,算例表明:当管外流场流速与管道顺流向振动速度值较接近时,不考虑流固耦合时的计算结果明显小于考虑流固耦合时的计算结果。分析认为,在管外流场流速与管道顺流向振动速度值较接近的情况下,管道的涡激振动计算宜采用非线性涡激力模型。

The expression of nonlinear lift forces for vortex-induced vibration, which takes fluid-structure interaction into consideration, is put forward via experiments on vortex-induced vibrations of pipelines. Using this expression, nonlinear dynamic responses of submarine pipelines are analyzed. The response of vortex-induced vibration of submarine pipelines is computed when fluid-structure interaction is considered and not considered, and the results are compared. The results show that the dynamic response of pipelines is much smaller when fluid-structure interaction is not considered, when the velocity of the external steady current approaches the horizontal vibration velocity of the pipeline. The analysis shows that a model of nonlinear lift forces should be adopted for the computation of vortex-induced vibration of pipelines, when the velocity of external steady current approaches the horizontal vibration velocity of pipelines.