Abstract: In order to explore the influence of deep sea T⁃tube flow difference and pipe diameter abrupt change on the flow characteristic parameters of the vertical pipe, a certain oil and gas field in the South China Sea was taken as the research object, and the numerical simulation method was used. The results show that the influence of flow rate difference is related to the sum of the total flow rate instead of the each flow; the effect of changing diameters of riser pipe on relevant parameters can be divided into three stages: DC=0.03 m, DC=0.06~0.12 m and DC=0.24 m. And when the vertical riser has a sudden change, the flow parameters are mainly related to its minimal pipe diameter.

Key words: Flow rate difference, Pipe diameter mutation, T?type pipe, Flow characteristics, Numerical simulation

摘要： 为探究深海T型管流量差异和管径突变对立管管内流动特性参数的影响，以南海某油气田为研究对象，通过数值模拟的方法进行了研究。结果表明，立管管内流动状态受到水平管段内总流量影响，与其分支管段流量的关系不明显；当水平管段管径保持不变的条件下，在立管直径DC为0.03 m、0.06～0.12 m和0.24 m时，立管相关参数的变化规律不同；当立管管径发生突变时，管内流动参数的变化主要与其最小管径有关。

关键词: 流量差异, 　管径突变, 　T型管, 　管内流动特性, 　数值模拟