Consistent initialization of mixed-dimensional multiphysics models for fractured reservoirs under geomechanical constraints and field measurements

TL;DR

This paper introduces a data-consistent initialization method for coupled multiphysics models of fractured reservoirs, aligning computational states with field measurements and geomechanical constraints to improve accuracy.

Contribution

It proposes a fixed point initialization strategy that reconstructs the reference configuration considering in-situ stress and measurements, enhancing model reliability.

Findings

Reduces deviations in fracture aperture predictions

Ensures consistency with field measurements and geomechanical constraints

Provides a foundation for extending to complex multiphase flow scenarios

Abstract

Modeling coupled processes in fractured porous media -- flow, deformation, fracture mechanics, and thermal/chemical effects -- often relies on mixed dimensional multiphysics formulations. These systems are nonlinear and depend on physical states and state dependent material laws. While in-situ field measurements consistently describe the deformed equilibrium configuration, computational models typically start from an idealized reference configuration and require explicit initialization of the in-situ stress state. This mismatch complicates initialization and linearization of constitutive laws. As a consequence, due to the two scale nature of fractured media, this can induce large deviations in fracture aperture directly impacting flow predictions. To address this, a discrete fracture model is introduced whose constitutive laws are expressed with respect to the unknown equilibrium state. This is paired with a fixed point initialization strategy that consistently reconstructs the reference configuration, consistent with both geomechanical constraints and field measurements up to load-path dependence. This data-consistent strategy provides a foundation for extending models to more complex scenarios, including multiphase and multicomponent flow in fractured reservoirs.