天然气液烃输送管道内非平衡气液相变机理与两相管流研究

项目名称： 天然气液烃输送管道内非平衡气液相变机理与两相管流研究

项目编号： No.51504206

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 矿业工程

项目作者： 贾文龙

作者单位： 西南石油大学

项目金额： 21万元

中文摘要： 天然气液烃（NGL）输送管道内的气液相变过程属于非瞬时平衡过程，采用等温瞬时相平衡假设分析NGL管道的两相流动不符合实际情况。项目采用理论与实验相结合的方法，开展NGL非平衡气液相变机理和两相管流研究。基于高温高压地层流体分析仪、多相流可视化环道实验平台，研究不同组成、压力、温度、流速等条件下，气液相特征参数的变化规律。根据分子动力学模拟方法以及非平衡态热力学、化学反应动力学理论，探究气液相界面区域内物质和热量传递的微观机理，建立气液相间非稳态物质、热量传递模型；结合双流体模型和最小熵产理论，建立伴随非平衡气液相变的两相管流模型；采用数值分析方法和CFD技术研究模型的求解方法。定量描述管道内NGL非平衡气液相变的发展过程和两相流动规律，为NGL输送管道的设计与运行管理提供理论和技术支撑。

中文关键词： 天然气液烃；管道输送；非平衡气液相变；两相流；数值模拟

英文摘要： The Natural Gas Liquid (NGL) liquid-vapor phase transition process is a non-instantaneous equilibrium process. Thus, the two-phase flow in the NGL transmission pipeline cannot be modeled by the method based on the assumption of isothermal and instantaneous phase equilibrium. In order to solve this problem, this project plans to research the NGL non-equilibrium phase transition mechanism and two-phase flow in the NGL pipeline by using the theoretical and experimental methods. Firstly, the DBR-JEFRI high pressure high temperature formation fluid analyzer and the multiphase pipe flow loop are utilized to research the relationship between the NGL composition, pressure, temperature, flow velocity and the two-phase feature parameters, which include the liquid and vapor phases’ compositions, volume proportion and phase transition lasting time. Secondly, the molecular dynamics simulation method, non-equilibrium thermodynamics and chemical kinetics theory are used to explore the microscopic mechanism of mass and heat transfer within the vapor-liquid interface region, and to build the mass and heat transfer prediction model. Thirdly, the non-equilibrium two-phase pipe flow model is developed through integrating the two-fluid flow model and the minimum entropy production theory. Finally, all above mathematical models are to be solved by the numerical method and CFD techniques. As a result, the evolution process of the NGL non-equilibrium phase transition and the features of the two-phase pipe flow can be obtained quantitatively. The achievements of this project will provide good theoretical and technical guidelines for both of the design and management of NGL transmission pipelines.

英文关键词： natural gas liquid; pipeline transmission;non-equilibrium liquid-vapor phase transition;two-phase flow;numerical simulation