Effects of angle patterns at fracture intersections on fluid flow nonlinearity and outlet flow rate distribution at high Reynolds numbers

Fluid flow tests on a series of one-inlet-two-outlet specimens with fracture intersections are conducted under conditions of high hydraulic gradient (J = 100–101) and high Reynolds number (Re = 104–105). The fluid flow through the intersections is recorded using a single lens reflex (SLR) camera. It was demonstrated that the intersection shapes can enhance the strong nonlinearity of the fluid flow at high J and high Re. The angle pattern, which is represented by the case of intersecting fractures, affects the ratio of the outlet flow rate distribution (ε). The detailed effects for all cases can be categorized into three models via quantitative analysis. The intersection shapes of model I angle patterns result in larger ε. However, the intersection shapes of model II and model III angle patterns result in smaller ε compared. In addition, the distribution fitting curve of the peak ε values is provided. A modified Gaussian distribution function is formulated to fit the experimental curves. Furthermore, the relationship between ε and the angle patterns is elaborated.