含水合物相变多相内流深水立管管内流动特征分析

Analysis of In-pipe Flow Characteristics of Hydrate-containing Multiphase Internal Flow in Deep Water Riser

在深海立管中,开采的天然气水合物受到环境因素和自身性质的影响,进行水合物的生成和分解等反应,使得管内流变成复杂的多相非平衡流,影响开采立管的安全性,容易引发安全事故。基于分子热力学,建立了天然气水合物在受温度压力变化影响下的生成分解相平衡模型,并在相平衡模型基础上考虑气液固三相的性质变化,得到由气液固各相连续方程、能量方程、动量方程组成的天然气水合物多相非平衡流控制方程。结合有限差分法分析得到不同参数对开采立管内多相流流动特性的影响规律。

Due to the influence of environmental factors and its own properties,natural gas hydrates in the deep water riser are formed or decomposed,resulting in the flow in the riser becoming a complex multiphase non-equilibrium flow.This can affect the safety of the mining riser and cause safety accidents.Based on molecular thermodynamics,a model for the formation and decomposition of natural gas hydrates under the influence of temperature and pressure changes was established.Then,considering the change of the properties of gas-liquid-solid three-phase,the governing equations of multiphase non-equilibrium flow of natural gas hydrate composed of continuous equation,energy equation and momentum equation of each phase were obtained.In this paper,combined with the finite difference method,the influence rule of different parameters on multiphase flow in riser was obtained.