A CFD Analysis on Proppant Transport in Fracture for Foam-Based Fracturing Fluid

Hydraulic fracturing is an unconventional process where the reservoir is fractured using a fracturing fluid to increase its permeability. Also, fracturing fluids are mixed with proppants to form slurries, which are then pumped into the fractures. Proppants sit in between the fractured walls and keep the fracture open after relieving the pressure. Foam-based fracturing fluids are one of the types of fracturing fluids which have high apparent viscosities and low specific gravity. Though foam-based fracturing fluids have non-newtonian rheology and low specific gravity, the proppant transporting capability of these fluids is not very clear. In this study, the transport and distribution of the proppant in the fracture are analyzed by the computational fluid dynamics (CFD) approach. A cuboidal ۳D fracture model, having a fixed length and height (۳۶۰ in. x ۱۰۶ in.), a uniform width (۰.۲۵ in.), with a fluid inlet of size ۶ in., is considered for this study. CFD simulations are done by varying the parameters namely proppant volume percentage in the slurry (۱۵, ۳۰, and ۴۵ %), inlet velocity (۵, ۱۰, and ۱۵ ft/s), proppant size (۳۰۰, ۶۰۰, and ۹۰۰ μm) and fracture width (۰.۱۵, ۰.۲۵, and ۰.۳۵ in.). CFD simulation results suggest higher inlet velocity, larger proppant volume fraction, relatively lesser proppant diameter, and optimal fracture width are better for having a well-distributed proppant system in a fracture.

Keywords:

Hydraulic Fracturing , Foam based Fracturing Fluids , Proppant Transport , Computational Fluid Dynamics.