2D HYDROMECHANICAL MODELING OF WATERFLOODING IN FRACTURING CONDITIONS USING FINITE ELEMENTS WITH HIGH ASPECT RATIO

Resumo

Waterflooding is a widely used methodology in the oil & gas industry and its main objective
is to guarantee the pore pressure maintenance in reservoirs during production as well as to sweep the oil
towards the producing wells. Injection of water in pressure conditions that exceed the reservoir fracture
pressure in operations known as IAFP (Injection Above Fracture Pressure) it's often necessary to ensure
the high injection rates required in secondary recovery processes. In order to model the hydromechanical
behavior of the fracking in the presence of producing wells, which particularly occurs in IAFP
operations, this work used the finite element method in two dimensions with high aspect ratio elements
and a constitutive law based on the tensile damage mechanics to model the opening and propagation of
hydraulic fractures. The fluid flow was described by Darcy's law and the fully coupled method was used
to solve the hydromechanical equations. Numerical examples with different injection rates and
production pressures were performed in order to verify the ability of the method to reproduce the
opening and propagation of fractures in the presence of producing wells. The results showed the method
was able to reproduce the opening and propagation of fractures in IAFP conditions and they also suggest
that in some cases the producing wells can play an important role in the propagation length of the
fractures.