顺应式垂直通路立管的动力响应优化研究

Dynamic response optimization of a compliant vertical access riser

海洋立管的动力响应优化要考虑复杂的环境载荷,如波浪、流以及浮体运动,有时还需考虑立管与海床的耦合作用,这个过程需要执行大量耗时较大的有限元分析,从而使动力优化的工作进展困难。针对此问题,本文将近似模型技术运用到FPSO的顺应式垂直通路立管(CVAR)的动力响应优化问题。优化以壁厚、管径等几何参数作为变量,优化目标是使总重量最小及等效应力在许用应力水平之下。研究给出了3种近似模型方法的比较分析,使得优化结果更具有可靠性。结果表明,3种近似模型方法的优化效果和效率彼此都非常接近,并且都能在CVAR的优化效果和减小耗时方面有出色表现。

Dynamic response optimization design of a marine riser should consider complex environmental loads such as wave,current,vessel motions,and sometimes the coupled riser-seabed interactions.Since the analysis process requires a large number of extremely time-consuming finite element analyses,the dynamic optimization for marine riser is quite difficult.The approximation method is applied to the dynamic response optimization of a compliant vertical access riser（CVAR）for FPSO.The optimization approach parameterizes the geometry in terms of several dimension variables like wall thickness,diameter and so on.The purpose of the optimization is to obtain the optimal dimensions which make the total weight of CVAR minimum and the maximum equivalent stress under allowable level.Three kinds of approximation methods are also compared with each other to make the results more reliable.The results indicate that the efficiency of using three approximation methods are very close to each other,and they all do an excellent job in optimizing the CVAR and significantly cutting down the consuming time.