Abstract Molecular diffusion plays a vital role in production from fractured reservoirs in all stages of recovery, especially for fractured reservoirs with small matrix sizes and unfavorable wettability conditions. Molecular diffusion can only be simulated by compositional reservoir simulators, which have historically employed a decoupled phase equilibrium-mass transfer model. Regardless of having higher performance, such a model cannot properly simulate intra- and cross-phase molecular diffusion. In the current research, a compositional fractured reservoir simulator, called Osiris, has been developed in C++ using the coupled formulation. After presenting the primary equations and algorithms, the performance of Osiris has been evaluated through a series of case studies. Utilizing MPI, Osiris could keep its runtime reasonable, despite the high computational demand of coupled modeling. Additionally, the simulation results of Osiris clearly prove the precision of the coupled modeling; and considerable effects of diffusive mass transfer on fractured reservoir performance.

中文翻译：

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耦合相平衡-传质模型的并行实现：裂缝性储层的高效准确模拟

摘要 分子扩散对裂缝性油藏各采收阶段的生产起着至关重要的作用，特别是对于基质尺寸较小和润湿性条件不利的裂缝性油藏。分子扩散只能通过成分油藏模拟器进行模拟，这些模拟器历来采用解耦相平衡-传质模型。尽管具有更高的性能，但这样的模型无法正确模拟内相和交叉相分子扩散。在当前的研究中，已使用耦合公式在 C++ 中开发了一种名为 Osiris 的组合裂缝油藏模拟器。在介绍了主要方程和算法之后，通过一系列案例研究评估了 Osiris 的性能。利用 MPI，Osiris 可以保持合理的运行时间，尽管耦合建模的计算需求很高。此外，Osiris 的仿真结果清楚地证明了耦合建模的精度；以及扩散传质对裂缝性储层性能的显着影响。