Wang Xiongsheng, Yin Cuicui, Wang Juan, Zheng Kaihong, Zhang Zhengrong, Tian Zhuo, Xiong Yongnan
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, China.
Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application, National Engineering Research Center of Powder Metallurgy of Titanium & Rare Metals, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510651, China.
Materials (Basel). 2023 Mar 24;16(7):2601. doi: 10.3390/ma16072601.
The viscous fingering phenomenon often occurs when a low-viscosity fluid displaces a high-viscosity fluid in a homogeneous porous media, which is an undesirable displacement process in many engineering applications. The influence of wetting gradient on this process has been studied over a wide range of capillary numbers (7.5 × 10 to 1.8 × 10), viscosity ratios (0.0025 to 0.04), and porosities (0.48 to 0.68), employing the lattice Boltzmann method. Our results demonstrate that the flow front stability can be improved by the gradual increase in wettability of the porous media. When the capillary number is less than 3.5 × 10, the viscous fingering can be successfully suppressed and the transition from unstable to stable displacement can be achieved by the wetting gradient. Moreover, under the conditions of high viscosity ratio ( > 0.01) and large porosity ( > 0.58), wetting gradient improves the stability of the flow front more significantly.
当低粘度流体在均匀多孔介质中驱替高粘度流体时，常常会出现粘性指进现象，这在许多工程应用中是一种不良的驱替过程。利用格子玻尔兹曼方法，在广泛的毛细管数（7.5×10至1.8×10）、粘度比（0.0025至0.04）和孔隙率（0.48至0.68）范围内，研究了润湿性梯度对该过程的影响。我们的结果表明，多孔介质润湿性的逐渐增加可以提高流动前沿的稳定性。当毛细管数小于3.5×10时，粘性指进可以成功抑制，通过润湿性梯度可以实现从不稳定驱替到稳定驱替的转变。此外，在高粘度比（>0.01）和大孔隙率（>0.58）的条件下，润湿性梯度能更显著地提高流动前沿的稳定性。
