In this paper, we present the results of benchmark simulations for plume spreading during CO₂ geo-sequestration conducted with the newly developed Australian CO₂ Geo-Sequestration Simulator (ACGSS). The simulator uses a hybrid finite element–finite volume (FEFVM) simulation framework, integrating an asynchronous local time stepping method for multi-phase multi-component transport and a novel non-iterative flash calculation approach for the phase equilibrium. The benchmark investigates four standard CO₂ storage test cases that are widely used to assess the performance of simulation tools for carbon geo-sequestration: (A) radial flow from a CO₂ injection well; (B) CO₂ discharge along a fault zone; (C) CO₂ injection into a layered brine formation; and (D) leakage through an abandoned well. For these applications, ACGSS gives results similar to well-established compositional simulators. Minor discrepancies can be rationalised in terms of the alternative, spatially adaptive discretisation and the treatment of NaCl solubility. While these benchmarks cover issues related to compositional simulation, they do not address the accurate representation of geologically challenging features of CO₂ storage sites. An additional 3D application scenario of a complexly faulted storage site demonstrates the advantages of the FEFVM discretisation used in the ACGSS for resolving the geometric complexity of geologic storage sites. This example also highlights the significant computational benefits gained from the use of the asynchronous time marching scheme.

在本文中，我们介绍了使用新开发的澳大利亚CO ₂地质固存模拟器（ACGSS）进行的CO ₂地质固存期间羽流扩散的基准模拟结果。该模拟器使用混合有限元-有限体积（FEFVM）模拟框架，集成了用于多相多组分传输的异步本地时间步长方法和用于相平衡的新颖的非迭代闪光计算方法。该基准研究调查了四个标准的CO ₂储存测试案例，这些案例被广泛用于评估碳地质封存模拟工具的性能：（A）来自CO ₂注入井的径流；（B）沿断层带的CO ₂排放；（C）一氧化碳₂注入成层的盐水中；（D）通过废弃井的泄漏。对于这些应用，ACGSS提供的结果与公认的成分模拟器相似。可以通过替代的空间自适应离散化和NaCl溶解度的处理来合理化较小的差异。尽管这些基准涵盖了与成分模拟有关的问题，但它们并未解决CO ₂地质挑战性特征的准确表示存放地点。复杂断层存储站点的其他3D应用场景展示了ACGSS中使用的FEFVM离散化解决地质存储站点的几何复杂性的优势。此示例还强调了使用异步时间行进方案所获得的显着计算优势。