关键词: 立方定律, 压力差损耗, 雷诺数, 偏转角度, 隙宽比, 岩体裂隙

Abstract: Calculation formula for different fracture flow is derived based on the cubic law. The formula is used to numerically analyze the flow pattern of several common fractures, including herringbone fracture, T-shaped fracture and crisscross fracture. The contraction and expansion effects caused by interaction and biased flow at the fracture branching and intersection points are believed to be the main cause for greater pressure loss. The formula is processed after non-dimensionalization by introducing the concept of differential pressure loss coefficient. It shows that Reynolds number, deflection angle of fracture and fracture width ratio are the main factors that influence the differential pressure loss coefficient. The analysis on variation of differential pressure loss coefficient shows: the magnitude of Reynolds number is directly proportional to the pressure dissipated at the intersection or branch of fracture; the pressure loss could be reduced by increasing the deflection angle of fracture; with increase of fracture width ratio of herringbone fractures and T-shaped fracture, the pressure loss at the fracture branching and intersection decreases, however, for crisscross fracture, the variation of pressure loss is opposite due to the interaction and biased flow.

Key words: cubic law, differential pressure loss, Reynolds number, deflection angle, fracture width ratio, rock fracture