基于LBM的通道内多孔介质交界面滑移效应研究

Study on slippage effect of porous media interface within the channel by Lattice Boltzmann Method

多孔介质与流体所构成复合区域内流体流动现象在自然界及社会许多行业之中广泛存在,研究含多孔介质通道内流体流动的问题具有重要意义。文章基于格子Boltzmann方法对局部填充多孔介质的通道内流体流动进行模拟,研究了不同工况条件下对多孔介质区域与纯流体交界面处的滑移效应变化规律,并采用编程进行数值模拟及结果验证,分析了不同Re数和孔隙率对多孔介质区域与纯流体交界面处的滑移效应。结果表明:速度滑移系数α始终为正,应力滑移系数β始终为负值;速度滑移系数α和应力滑移系数β的数值随Re数和孔隙率ε增大时的变化趋势不同,但滑移效应的变化趋势相同,即速度滑移效应和应力滑移效应都随Re数的增大而增强,随孔隙率ε的增大而减弱。

Fluid flow phenomenon on the composite area of porous media and fluid is so widespread in nature and human society. The study on the flow in porous media channels has important practical significance. The model on channel partially numerically by lattice Boltzmann method. Study filled with structured porous layer was simulated on the change rule of porous media area and pure fluid interface slippage effect under different conditions, numerical simulation by programming, analyzing principally the impact of different Re number and the porosity 8 of the porous medium on the slip effect at the porous/fluid interface. The numerical results show that the velocity slip coefficient is always positive. On the contrary, the stress slip coefficient is always negative; the change trends of velocity slip and stress slip coefficient with Re and the porosity e are different, instead, the tendency of the slip effect is the same, which means that the velocity slip effect and the stress slip effect are enhanced with the increase of Re number, and decreases with the increase of the porosity ε.