针对高低温流体在多路阀内混合的流体流态、热量传递规律等影响油气生产集输的问题的研究尚不充分。以某海洋油气井口平台集输多路阀为研究对象,运用计算流体动力学(Computational Fluid Dynamics,CFD)方法和工具,对多路阀内冷热多相流的混合集输过程进行数值模拟。通过分析不同比例冷热物流集输工况下的相体积分数、温度、黏度和流速等流场特性及变化规律，得到进口流量、气液比例及多路阀结构直接影响集输流型和流速,流量增加导致的集输出口处流速显著提升和流速方向分散问题,需在设计多路阀时优化集输口角度以保障集输稳定性和降低能耗;冷流(低温气井流体)与热流(高温油井流体)在多路阀内部空间换热不均匀,局部出现低温,且随着低温气体比例增加,造成部分油水凝结和增加腐蚀风险,需考虑多路阀前混合或增加药剂等措施避免形成水合物及凝结。研究成果为井口平台冷热多相流生产集输工艺优化提供了理论参考。

The effect of flow patterns, heat transfer characteristics, and other factors related to the mixing of cold and hot multiphase flows within multiport selector valve(MSV) on production gathering and transportation remain insufficiently studied. Taking the gathering MSV on a certain offshore oil and gas well platform as the study object, this study uses Computational Fluid Dynamics(CFD) methods and tools to conduct a numerical simulation of the mixed gathering and transportation process of cold and hot multiphase flows within the MSV. By analyzing flow field characteristics—including the distribution and variation trends of phase volume fraction, temperature, viscosity, and velocity—under different ratios of cold and hot stream conditions, the results indicate that inlet flow rate, gas-liquid ratio, and MSV structure directly affect the flow patterns and velocity direction distributions. An increase in inlet flow rate significantly raise the flow velocity at the gathering outlet and causes velocity direction dispersion. Therefore, optimizing the outlet angle of MSV is necessary to ensure system stability and reduce energy consumption. Heat transfer inside the MSV space is non-uniform during mixing of cold(low-temperature gas well fluids) and hot(high-temperature oil well fluids) streams, resulting in localized low-temperature regions. As the proportion of cold streams increases, risks of hydrate formation, corrosion, and freezing rise. Methods such as premixing the two streams or injecting chemicals into streams upstream of the MSV shall be taken into account to avoid hydrate formation and freezing. The research findings provide a theoretical reference for the optimization of the cold and hot multiphase flow production gathering and transportation process in wellhead platforms.