Effects of Slip Length and Inertia on the Permeability of Fracture with Slippery Boundary Condition

International Journal of Environmental Research and Public Health

Huan Qi¹  Benhua Liu²  Linxian Huang²  Hao Zhan²  Yiran Liu³  Zhizheng Liu⁴  Zhengrun Wei⁴ 

[1] 801 Institute of Hydrogeology and Engineering Geology, Shandong Provincial Bureau of Geology & Mineral Resources, Jinan 250014, China;School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China;School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China;Shandong Institute of Geological Survey, Jinan 250013, China;

关键词: slip length;    inertial force;    fracture;    nonlinear flow;    permeability;   

DOI  :  10.3390/ijerph17113817

来源: DOAJ

【 摘 要 】

Although the slippery boundary condition (BC) has been validated to enhance fracture permeability (k), the coupling effects of heterogeneous slippery BC and inertia on k remain less understood. We used computational fluid dynamics to investigate the competing roles of slippery BC and inertial forces in controlling k evolution with increasing pressure gradient by designing six cases with different slip length scenarios for a two-dimensional natural fracture. Our results suggest that pronounced inertial effects were directly related to and demonstrated by the growth of recirculation zone (RZ); this caused flow regimes transitioning from Darcy to non-Darcy and significantly reduced k, with an identical tailing slope for six cases, regardless of the variability in slip lengths. Moreover, the slippery BC dominantly determine the magnitude of k with orders depending on the slip length. Lastly, our study reveals that the specific k evolution path for the case with a varying slip length was significantly different from other cases with a homogeneous one, thus encouraging more efforts in determining the slip length for natural fractures via experiments.

【 授权许可】

Unknown