We conducted coupled flow-geomechanics simulations to update the stress and strain fields as the reservoir depletes. This information can be used to modify reservoir properties or to consider for future infill or refracturing jobs. Visualizations include permeability, displacement, stress and strains values and were done using ResInsight.
A novel methodology to perform simulations of coupled flow-geomechanics in LGR grids has been
implemented in OpenSim simulator. The workflow consist in projections of the pressure solution from the LGR onto a coarse geomechanics grid to solve the poroelastic problem, then use the coarse solution as boundary
conditions for the LGR cells and, finally, solve the poroelastic problem in each LGR cell.
On the formulation we consider a realistic situation that mimics production in a tight reservoir that
contains a hydraulic fracture.
One can see in Figures 9(a)-(c) the evolution of the pressure field in the tartan grid, with a notorious
depletion around the fracture and part of the SRV. The same effect is captured in the LGR model (see
Figures 9(d)-(f)), with much less cells and better CPU performance (10x CPU reduction).
Visualizations are made with ParaView.
Depletion in a model of a single fracture with SRV : Pressure change comparison in a fully
refined tartan grid vs a Coarse grid with LGR cells around the well.
Reference:
"Two-Way Coupling of Flow and Geomechanics Simulations with Local Grid Refinement". Paper published in ECMOR XVI 2018 – 16th European Conference on the Mathematics of Oil Recovery, Barcelona, Spain 3–6 September 2018.