FPSO卧式三相分离器内液相晃荡抑制的数值模拟研究

Numerical simulation on the liquid sloshing suppression in horizontal three-phase separator mounted on FPSO

由于深海浮式油气生产平台的特殊结构形式,这对平台上的油气处理装置设计提出了更高要求。该文针对FPSO卧式三相分离器内油水相的晃荡规律及其抑制问题,建立了基于VOF方法的适用于平台任意自由度晃动条件下分离器内油水相晃荡分析的数值计算模型,用数值试验的方法分别对FPSO卧式三相分离器在不同放置位置、长径比以及不同气液和油水界面高度等情形下的油水相晃荡位移响应特性进行了对比研究。结果表明,为主动抑制FPSO卧式三相分离器内油水相晃荡,应尽可能使分离器靠近FPSO的纵向和横向旋转中心、分离器的长径比不宜超过3并在满足油气水各相分离质量的前提下应尽量增大气液界面高度并降低水相液位高度。

The higher design requirements for oil＆gas process equipments on floating production platform have been put forward, due to the special structure of platforms. To solve the liquid sloshing suppression problem in horizontal three-phase separators used on FPSO, the numerical model based on the VOF method, which is applied to simulate the liquid sloshing in separators under any multi-degree of freedom of external excitations produced by FPSO, has been established. The response characteristics of liquid sloshing in separators under different locations, ratio of length to diameter, level settings of gas/liquid and oil/water interfaces have been studied. The results show that, in order to suppress the liquid sloshing initiatively, horizontal three-phase separators should be located near the Center of Rotation （COR） of FPSO, the ratio of length to diameter of the separator is recommended no more than three, and the height of gas/liquid interface should be improved as higher as possible while the height of water phase should be reduced as lower as possible to assure the quality of three-phase separation. The numerical model established and corresspongding results can be used to provide new analysis means and design references for horizontal three-phase separators used on FPSO in the future.