中文摘要：

为了研究层流状态下粗糙单裂隙面的渗流特性,基于格子Boltzmann方法,建立了压力作用下单裂隙面渗流的数值模型。采用D2Q9模型模拟离散速度分布方向,在宏观尺度上,上、下边界设置为不透水边界（ux=uy=0）,左、右边界为压力边界（左侧压力p（in）大于右侧压力p（out））在微观尺度上,左、右边界及光滑裂隙表面采用非平衡态外推格式,粗糙裂隙表面采用标准反弹格式。编制了相应的计算程序,验证了光滑平板裂隙流的立方定律。采用分段随机裂隙长及裂隙宽的方法生成了粗糙裂隙面,并基于格子Boltzmann方法研究了不同粗糙裂隙面方案的渗流特性。研究结果表明：对于粗糙裂隙面,渗流特征极大程度取决于裂隙表面形貌,随着相对粗糙度的增加,裂隙渗流规律明显偏离立方定律。为此,考虑裂隙面相对粗糙度的影响,根据不同裂隙粗糙面方案的数值计算结果,提出了层流状态下粗糙裂隙面渗流的立方定律修正公式,为系统研究复杂粗糙裂隙的水力特性奠定了一定的基础。

英文摘要：

To investigate seepage characteristics of a single rough fracture, based on lattice Boltzmann method, a numerical model is established to analyze the water flow in laminar under pressure. The D2Q9 model is applied to simulate the discrete velocity direction. On the macroscopic-scale, the upper and lower boundaries （ux =Uy =0） are assumed to be impermeable, and the left and right boundaries are controlled by pressure （i.e., the pressure on the left side is larger than that on the right side）. On the microscopic-scale, the non-equilibrium extrapolation scheme is set on the pressure boundary and smooth fracture surface boundary, and the standard bounce-back scheme is set on the rough fracture surface boundary. The corresponding program is compiled to verify the classical cubic law of smooth plate fracture flow. The rough fracture surface is generated by setting piecewise random length and random width, and seepage characteristics of different rough fracture surfaces are discussed in detail. The results show that fracture surface roughness greatly affects seepage characteristics. With the increase of relative roughness, the deviation from cubic law becomes more obvious. Therefore, by considering the effect of relative fracture surface roughness, the modified cubic law is proposed according to numerical results of different schemes of rough fracture surface. This study lays the foundation for further research on the complex hydraulic characteristics of rough fracture.