Hydraulic fracture propagation in highly permeable formations, with applications to tip screenout

摘要

This paper describes hydraulic fracture propagation in a permeable medium by means of the so-called tip screenout technique. A simple self-consistent mechanical model that allows us to clarify mechanics of proppant bridging at the fracture tip and explain some of the discrepancies between simulation and treatment data is presented. Slurry flow in the fracture is calculated using a single-phase approach with an effective viscosity, taking into account filtrate leakoff across the fracture faces, and kinetics of filter cake growth. The Khristianovich-Zheltov-Geertsma-De Klerk (KGD) fracture model is formulated in a moving coordinate system with a fixed number of nodes, and is solved iteratively using a mixed explicit-implicit finite difference technique. Results of numerical experiments and model verification are presented.