Relative permeabilities and coupling effects in steady-state gas-liquid flow in porous media: A lattice Boltzmann study
Relative permeabilities and coupling effects in steady-state gas-liquid flow in porous media: A lattice Boltzmann study
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多孔介质中稳态气液流动的相对渗透率和耦合效应：格子玻尔兹曼研究
DOI：
10.1063/1.3225144
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发表时间：
2009-09-01
影响因子：
4.6
通讯作者：
Lu, Xi-yun
中科院分区：
文献类型：
--
作者：
Huang, Haibo;Lu, Xi-yun
本文采用shan - chen型单组分多相晶格玻尔兹曼模型，研究了多孔介质中非混相两相（气液）流动的粘滞耦合效应。利用该模型可以模拟密度比高达56的多孔介质中的两相流动，且固体壁面气液界面的接触角是可调的。为了研究黏性耦合效应，在不同的毛细管数、润湿性和黏度比下，获得了共、逆流稳态两相流模式和相对渗透率随润湿饱和度的函数。共流相对渗透率通常大于逆流相对渗透率。在共流和逆流中，相反的阻力效应和不同的孔隙级饱和度分布可能是造成这种差异的原因。结果表明，在共流和逆流情况下，强湿情况下，k（nw）随驱动力和粘度比的增大而增大。然而，对于中性潮湿的情况，k（nw）和k(w)的变化更为复杂。不同的初始孔隙级饱和度分布会影响最终稳态分布，从而影响相对渗透率。用共流和逆流稳态流实验来确定广义相对渗透率似乎是不正确的。
In this paper, the viscous coupling effects for immiscible two-phase (gas-liquid) flow in porous media were studied using the Shan-Chen-type single-component multiphase lattice Boltzmann model. Using the model, the two-phase flows in porous media with density ratio as high as 56 could be simulated and the contact angle of the gas-liquid interface at a solid wall is adjustable. To investigate viscous coupling effects, the co- and countercurrent steady-state two-phase flow patterns and relative permeabilities as a function of wetting saturation were obtained for different capillary numbers, wettabilities, and viscosity ratios. The cocurrent relative permeabilities seem usually larger than the countercurrent ones. The opposing drag-force effect and different pore-level saturation distributions in co- and countercurrent flows may contribute to this difference. It is found that for both co- and countercurrent flows, for strongly wet cases and viscosity ratio M>1, k(nw) increase with the driving force and the viscosity ratio. However, for neutrally wet cases, the variations of k(nw) and k(w) are more complex. It is also observed that different initial pore-level saturation distributions may affect final steady-state distribution, and hence the relative permeabilities. Using the cocurrent and countercurrent steady flow experiments to determine the generalized relative permeabilities seems not correct.