不同浮力下水下悬浮丛式管汇水动力分析

Hydrodynamic analysis of underwater suspension cluster manifold under different buoyancy

本文利用OracleFlex软件建立了水下悬浮丛式管汇概念模型,分析了升沉运动下的悬链线参数特性,选择不同参数关系进行模拟,并根据不同油气密度和悬浮范围计算了管汇中浮筒质量的许用范围。基于Morison公式和凝集质量法,得到了浮筒质量许用范围内极端油气密度下管汇悬浮高度、偏移量、偏转角度和柔性立管最大拉力与最小弯曲半径的变化规律。根据悬链线参数关系优选外输管线悬跨长度,调节浮筒质量差使管汇平衡,得到了管汇稳定性主要参数在海流和极端油气密度下的变化规律。结果表明,通过优选外输管线悬跨长度与调节浮筒质量差,可使管汇满足稳定系泊的要求,从而实现水下悬浮丛式管汇的全空间布局。

In this paper,a conceptual model of underwater suspension cluster manifold is established by using Oracle Flex software,the characteristics of catenary parameters under heave motion are analyzed,and the analog calculations are carried out by selecting various parameter relationships,hence obtaining the allowable scope of manifold pontoon mass according to different hydrocarbon densities and suspension ranges.Based on the Morison formula and the agglomeration mass method,the variation rules of the manifold suspension height,offset,deflection angle,and the maximum tensile force and minimum bending radius of flexible risers under extreme oil and gas densities within the allowable mass of the buoy are obtained.The cantilever span of the external transmission pipeline is optimized according to the parameters relationship of the catenary,and the buoy mass is adjusted properly to balance the manifold,hence obtaining the change laws of the main manifold stability parameters under the ocean current and extreme oil and gas densities conditions.The results show that by optimizing the cantilever span length of external transmission pipeline and adjusting the buoy mass difference,the manifold can satisfy the requirements of stable mooring,thereby realizing the full space layout of the underwater suspension cluster manifold.