Print Email Facebook Twitter Relative Permeability of Near-Miscible Fluids in Compositional Simulators Title Relative Permeability of Near-Miscible Fluids in Compositional Simulators Author Alzayer, Ala N. (Stanford University; Saudi Aramco) Voskov, D.V. (TU Delft Reservoir Engineering; Stanford University) Tchelepi, Hamdi A. (Stanford University) Date 2018 Abstract Miscible gas injection is one of the most effective enhanced oil recovery techniques. There are several challenges in accurately modeling this process, which occurs in the near-miscible region. The adjustment of relative permeability for near-miscible processes is the main focus of this work. The dependence of relative permeability on phase identification can lead to significant complications while simulating near-miscible displacements. We present an analysis of how existing methods incorporate compositional dependence in relative permeability functions. The sensitivity of the different methods to the choice of reference points is presented with guidelines to limit the modification of the relative permeabilities to physically reasonable values. We distinguish between the two objectives of reflecting near-miscible behavior and ensuring smooth transitions across phase changes. We highlight an important link that combines the two objectives in a more general framework. We make use of Gibbs free energy as a compositional indicator in the generalized framework. The new approach was implemented in an automatic differentiation general purpose research simulator and tested on a set of near-miscible gas-injection problems. We show that including compositional dependencies in the relative permeability near the critical point impacts the simulation results with significant improvements in nonlinear convergence. Subject CompositionalGas injectionGibbs free energyMiscibleRelative permeabilitySimulationSurface tension To reference this document use: http://resolver.tudelft.nl/uuid:ecf51e23-000c-488b-b24a-d11cb75b4479 DOI https://doi.org/10.1007/s11242-017-0950-9 Embargo date 2019-04-01 ISSN 0169-3913 Source Transport in Porous Media, 122 (3), 547–573 Part of collection Institutional Repository Document type journal article Rights © 2018 Ala N. Alzayer, D.V. Voskov, Hamdi A. Tchelepi Files PDF TIPM_Manuscript.pdf 4.69 MB Close viewer /islandora/object/uuid:ecf51e23-000c-488b-b24a-d11cb75b4479/datastream/OBJ/view