Urban drainage modelling is essential for effective city planning and flood management. The increasing complexity of urban environments and the growing availability of high-resolution data have led to the need to develop more sophisticated and freely accessible urban drainage models. This paper presents the parallel implementation of Iber-SWMM, a freely distributed integrated 2D/1D urban drainage model for modelling surface and sewer flows and their interactions. Iber-SWMM constitutes an advance in the field by incorporating a fully distributed hydrological approach, advanced roof modelling tools, and GIS interoperability, offering a comprehensive solution for urban hydrodynamics. Originally designed for research in small urban drainage models due to CPU limitations, Iber-SWMM has now been enhanced with High Performance Computing (HPC) techniques. This allows for the simulation of high-resolution urban models with fine meshes comprising millions of elements, essential for accurate representation of complex urban geometries. We validated the model through laboratory-scale tests and two city-scale scenarios, providing detailed input data and demonstrating the applicability of the model in real-world situations. Our results show that the GPU-accelerated version achieves simulation speeds up to 200 times faster than the sequential version for large models. For instance, in a city-scale scenario with approximately 6 million cells, 3000 nodes, and 3000 links, simulation time was reduced from 72 h to just 20 min. To ensure result consistency and assess convergence, we conducted simulations using low, medium, and high-resolution computational meshes for each case study. Our findings indicate that both parallel and sequential versions produce consistent results, with convergence typically achieved at medium to high resolutions. Notably, we observed that for very large models, the computation of the drainage network in SWMM can become a bottleneck, suggesting an area for future optimization. By enabling the simulation of high-resolution urban models with millions of elements up to 200 times faster than sequential versions, this study bridges the gap between academic research and practical urban planning, empowering stakeholders to conduct more detailed, city-wide simulations, and ultimately contributing to faster urban flood risk management.

中文翻译：

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IberSWMM+：用于城市环境中 2D-1D 洪水建模的高性能计算求解器


城市排水建模对于有效的城市规划和洪水管理至关重要。城市环境日益复杂和高分辨率数据的日益普及，导致需要开发更复杂且可自由访问的城市排水模型。本文介绍了 Iber-SWMM 的并行实现，这是一种免费分发的集成 2D/1D 城市排水模型，用于对表面和下水道流量及其交互进行建模。Iber-SWMM 通过整合完全分布式水文方法、先进的屋顶建模工具和 GIS 互操作性，为城市流体动力学提供了全面的解决方案，从而构成了该领域的进步。由于 CPU 限制，Iber-SWMM 最初设计用于小型城市排水模型的研究，现在已通过高性能计算 （HPC） 技术得到增强。这允许使用包含数百万个单元的精细网格来模拟高分辨率城市模型，这对于准确表示复杂的城市几何图形至关重要。我们通过实验室规模的测试和两个城市规模的情景验证了该模型，提供了详细的输入数据并展示了该模型在实际情况下的适用性。我们的结果表明， GPU 加速版本的仿真速度比大型模型的 Sequential 版本快 200 倍。例如，在具有大约 600 万个单元、3000 个节点和 3000 个链路的城市规模场景中，仿真时间从 72 小时缩短到仅 20 分钟。为了确保结果的一致性并评估收敛性，我们为每个案例研究使用低、中、高分辨率计算网格进行了模拟。 我们的研究结果表明，并行和顺序版本都产生了一致的结果，通常在中高分辨率下实现收敛。值得注意的是，我们观察到，对于非常大的模型，SWMM 中排水网络的计算可能成为瓶颈，这表明了未来需要优化的领域。通过模拟具有数百万个元素的高分辨率城市模型，其速度比顺序版本快 200 倍，本研究弥合了学术研究和实际城市规划之间的差距，使利益相关者能够进行更详细的城市范围模拟，并最终有助于加快城市洪水风险管理。