Computational Algorithm for the Anticipation of the Fluid-Lag Zone in Hydraulic Fracturing Treatments

In this paper, a computational algorithm based on the eXtended Finite Element Method (X-FEM) is developed to study the fluidlag zone involved in hydraulic fracturing treatments. The fluid-lag zone, caused due to the high pressure gradient in the vicinity of the hydrofracture tip, is primarily treated by the imposition of the vapor pressure. The capillary action at the flow front is captured by inclusion of the surface tension effects. The overlap of the hydrofracture faces, particularly within the fluid-lag region, is prevented using an X-FEM penalty algorithm. The governing equations of the hydrofracture inflow and the surrounding domain are solved in a sequential order called the staggered Newton strategy. Finally, the performance and the accuracy of the proposed numerical approach are explored by means of numerical simulation. (c) 2018 American Society of Civil Engineers.