Lattice Boltzmann Simulation of Multicomponent Porous Media Flows With Chemical Reaction
Lattice Boltzmann Simulation of Multicomponent Porous Media Flows With Chemical Reaction
复制标题
DOI：
10.3389/fphy.2021.715791
复制
发表时间：
2021-08
影响因子：
3.9
通讯作者：
Timan Lei;K. Luo
中科院分区：
文献类型：
--
作者：
Timan Lei;K. Luo
多孔介质中的化学反应流动是许多自然、工业和科学领域中遇到的基本现象。对于这样的流动，大多数现有的研究使用连续假设，并集中在宏观尺度上的体积平均属性。考虑到实际情况下复杂的多孔结构和流固相互作用，本研究发展了一个复杂的格子Boltzmann（LB）模型来模拟多孔介质中的反应流动在孔隙尺度上。在本模型中，单独的LB方程建立的多组分流动和化学物种的演变，源项推导的热量和质量传递，边界计划制定的表面反应，和修正项的温度依赖性密度。因此，目前的LB模型提供了一种能力，以捕捉孔隙尺度的可压缩/不可压缩流体运动，可混溶流体之间的均匀反应，在多孔介质中的流体-固体界面的非均相反应的信息。研究了均相反应下密度指进的不同情况，澄清了粘度对比的影响。此外，通过引入热流，模拟了多孔介质中固体焦炭的燃烧。在焦炭燃烧过程中，流体粘度受到传热传质的影响，导致不稳定的燃烧锋。
Flows with chemical reactions in porous media are fundamental phenomena encountered in many natural, industrial, and scientific areas. For such flows, most existing studies use continuum assumptions and focus on volume-averaged properties on macroscopic scales. Considering the complex porous structures and fluid–solid interactions in realistic situations, this study develops a sophisticated lattice Boltzmann (LB) model for simulating reactive flows in porous media on the pore scale. In the present model, separate LB equations are built for multicomponent flows and chemical species evolutions, source terms are derived for heat and mass transfer, boundary schemes are formulated for surface reaction, and correction terms are introduced for temperature-dependent density. Thus, the present LB model offers a capability to capture pore-scale information of compressible/incompressible fluid motions, homogeneous reaction between miscible fluids, and heterogeneous reaction at the fluid–solid interface in porous media. Different scenarios of density fingering with homogeneous reaction are investigated, with effects of viscosity contrast being clarified. Furthermore, by introducing thermal flows, the solid coke combustion is modeled in porous media. During coke combustion, fluid viscosity is affected by heat and mass transfer, which results in unstable combustion fronts.