To solve the problem that it is hard to determine perforation numbers at clusters due to the perforation erosion effects during hydraulic fracturing treatment,we set up numerical examples with a fully-three-dimensional simulator FrackOptima and a perforation erosion model established in a previous study.We investigated the effects of perforation erosion on six resulting parameters of fracturing treatment by using the boundary element method for discretization and the time-step algorithm for numerical simulation of coupled mechanics of solid and fluid.The six resulting parameters are configurations of final fractures,fracturing-fluid distribution,perforation pressure drop,perforation diameter,discharge coefficient,and downhole pressure.The results demonstrate that the effects of perforation erosion are negligible during conventional non-limited-entry treatment because both the value of perforation pressure drop and its instant change induced by perforation erosion are small,while they can not be neglected in simultaneous multi-fracture limited-entry treatment for development of unconventional reservoirs because the value of perforation pressure drop is large and its instant change induced by perforation erosion is significant.An eight-perforation per cluster produces appropriate perforation pressure drop to mitigate stress shadow effects,leading to a relatively uniform propagation of multiple fractures and ensuring downhole pressures in safe range for practical fracturing.
维普
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