Department of Civil and Environmental Engineering, Imperial College London, Skempton building, South Kensington Campus, London SW7 2AZ, UK.
Water Sci Technol. 2010;62(9):2106-14. doi: 10.2166/wst.2010.382.
Lead time between rainfall prediction results and flood prediction results obtained by hydraulic simulations is one of the crucial factors in the implementation of real-time flood forecasting systems. Therefore, hydraulic simulation times must be as short as possible, with sufficient spatial and temporal flood distribution modelling accuracy. One of the ways to reduce the time required to run hydraulic model simulations is increasing computational speed by simplifying the model networks. This simplification can be conducted by removing and changing some secondary elements using network simplification techniques. The emphasis of this paper is to assess how the level of urban drainage network simplification influences the computational time and overall simulation results' accuracy. The models used in this paper comprise a sewer network and an overland flow drainage system in both 1D/1D and 1D/2D approaches. The 1D/1D model is used as the reference model to generate several models with different levels of simplifications. The results presented in this paper suggest that the 1D/2D models are not yet suitable to be used in real-time flood prediction applications due to long simulation time, while on the other hand, the simplified 1D/1D models show that considerable reductions in simulation time can be achieved without compromising simulation results (flow and water depth) accuracy.
从降雨预测结果到水力模拟得出的洪水预测结果的时间间隔是实时洪水预报系统实施的关键因素之一。因此，水力模拟时间必须尽可能缩短，同时具有足够的时空洪水分布建模精度。减少水力模型模拟所需时间的一种方法是通过简化模型网络来提高计算速度。这种简化可以通过使用网络简化技术来删除和更改一些次要元素来实现。本文的重点是评估城市排水管网简化的程度如何影响计算时间和整体模拟结果的准确性。本文中使用的模型包括污水管网和漫流排水系统，分别采用 1D/1D 和 1D/2D 方法。1D/1D 模型用作参考模型，生成具有不同简化程度的多个模型。本文提出的结果表明，1D/2D 模型由于模拟时间长，尚不适用于实时洪水预测应用，而另一方面，简化的 1D/1D 模型表明，在不影响模拟结果（流量和水深）准确性的情况下，可以大大缩短模拟时间。
