不同节理粗糙度系数的裂隙渗流规律研究

Research on regulation of fracture seepage in different joint roughness coefficients

裂隙的研究对石油开采、水利工程以及地下空间的利用都具有重要的意义。真实裂隙表面粗糙的几何形态会影响流体的流动特性及裂隙的传导能力,立方体定律难以满足使用条件。根据节理粗糙度(JRC)标准剖面轮廓曲线,采用逆向数字化建模方法,开展仿真模拟不同JRC裂隙渗流规律的研究。结果表明:作用在不同粗糙度裂隙两端的压差恒定时,随着节理粗糙度的增加裂隙内流体的流量逐渐减小;流入不同粗糙度裂隙单位体积流量恒定时,随着粗糙度的增加,作用在裂隙两端的压差逐渐增大;模拟结果与实验结果相对比,得出裂隙机械宽度与流量之间的关系曲线表现出明显的非线性特征,两条趋势线相吻合,均符合对数关系。

The research on fracture has important significance to oil development, irrigation works and underground space utilization. While the geometrical form of actual roughness of fracture surface will influence the specification of liquid flowing and conduction capability of fracture, cubic law is failed to be executed. Based on the standard section outline curve of JRC, various researches on different JRC regulation were performed via reverses digital modeling method. The result showed that when a consistent pressure differential acts on both sides of fractures owning different roughness, liquid flow is gradually reduced along with the increase of joint roughness , the differential pressure on both sides will be gradually increased with the increase of surface roughness when the flow that running into various certain surfaces is fixed. Comparing simulation result with experimental one, the relationship curve between fracture mechanical width and flow showed obvious non -linear feature, two lines match well and accord with logarithmic relation.