The influence of rock seepage must be considered in geotechnical engineering, and understanding the fluid flow in rock fractures is of great concern in the seepage effect investigation. This study is aimed at developing a model for inversion of rock fracture domains based on digital images and further study of non-Darcy flow. The visualization model of single rock fracture domain is realized by digital images, which is further used in flow numerical simulation. We further discuss the influence of fracture domain geometry on non-Darcy flow. The results show that it is feasible to study non-Darcy flow in rock fracture domains by inversion based on digital images. In addition, as the joint roughness coefficient (JRC) increases or the fracture aperture decreases, distortion of the fluid flow path increases, and the pressure gradient loss caused by the inertial force increases. Both coefficients of the Forchheimer equation decrease with increasing fracture aperture and increase with increasing JRC. Meanwhile, the critical Reynolds number tends to decrease when JRC increases or the fracture aperture decreases, indicating that the fluid tends to non-Darcy flow. This work provides a reference for the study of non-Darcy flow through rock fractures.

中文翻译：

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数字图像反演的单岩裂域非达西流数值模拟

岩土工程必须考虑岩石渗流的影响，了解岩石裂缝中的流体流动是渗流效应研究的重点。本研究旨在开发一种基于数字图像的岩石断裂域反演模型，并进一步研究非达西流。单岩裂隙域的可视化模型通过数字图像实现，进一步用于流动数值模拟。我们进一步讨论了裂缝域几何形状对非达西流的影响。结果表明，基于数字图像反演研究岩石裂缝域中的非达西流是可行的。此外，随着接头粗糙度系数（JRC）的增加或裂缝孔径的减小，流体流动路径的畸变增加，惯性力引起的压力梯度损失增加。Forchheimer 方程的两个系数都随着裂缝孔径的增加而减小，随着 JRC 的增加而增加。同时，当 JRC 增大或裂缝孔径减小时，临界雷诺数趋于减小，表明流体趋于非达西流动。该工作为非达西流穿过岩石裂缝的研究提供了参考。