Pore-Scale Thermo-Hydro-Mechanical Simulation of Heavy Oil Displacement in 3D Anisotropic Porous Media

Three-dimensional synthetic porous models were generated using an improved Quartet Structure Generation Set (QSGS) method to examine heavy oil displacement. Flow and heat transfer were coupled, with a one-way thermoelastic response on a fixed geometry. Between-axis anisotropy was distinguished from the response to inlet–outlet reversal. In the main model, reversal changed absolute permeability by no more than 0.062%, whereas water saturation indicators at 0.5 s differed by 7.2%, 1.2%, and 31.3% along X, Y, and Z. An additional ensemble of 15 realizations was compared using saturation-based incremental recovery referenced to each initialized oil volume. Within the common supported range up to 2.90 injected pore volumes (PV), the one-sided growth design showed negative reverse-minus-forward gaps in all five realizations at every evaluated checkpoint from 0.5 PV. At 1 PV, the mean gap was −17.08 percentage points with a sample standard deviation of 6.20. The isotropic and symmetric designs showed smaller means with mixed individual signs. These results support directional sensitivity within the tested structures while distinguishing fixed-time throughput effects from matched-PV comparisons. The growth-probability trend remains an association for the selected geometries, and the finite-time results do not establish ultimate recovery.