Fluid velocity based simulation of hydraulic fracture: a penny shaped model-part I: the numerical algorithm

Meccanica. 2018;53(15):3615-3635. doi: 10.1007/s11012-018-0899-y. Epub 2018 Oct 22.

Abstract

In the first part of this paper, a universal fluid velocity based algorithm for simulating hydraulic fracture with leak-off, previously demonstrated for the PKN and KGD models, is extended to obtain solutions for a penny-shaped crack. The numerical scheme is capable of dealing with both the viscosity and toughness dominated regimes, with the fracture being driven by a power-law fluid. The computational approach utilizes two dependent variables; the fracture aperture and the reduced fluid velocity. The latter allows for the application of a local condition of the Stefan type (the speed equation) to trace the fracture front. The obtained numerical solutions are carefully tested using various methods, and are shown to achieve a high level of accuracy.

Keywords: Hydraulic fracture; Leak-off; Penny-shaped crack; Power law fluid; Speed equation; Universal algorithm.