Benchmarking 2D hydraulic models for urban flooding
Benchmarking 2D hydraulic models for urban flooding
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DOI：
10.1680/wama.2008.161.1.13
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发表时间：
2008-02-01
影响因子：
1.1
通讯作者：
Mason, D. C.
中科院分区：
文献类型：
--
作者：
Hunter, N. M.;Bates, P. D.;Mason, D. C.
本文描述了六个二维（2D）水力模型（DIVAST, DIVAST- tvd， TUFLOW， JFLOW， TRENT和LISFLOOD-FP）在模拟密集城市化地区地表流动方面的基准测试。这些模型应用于英国苏格兰格拉斯哥市一个1.0公里× 0.4公里的城市集水区，并用于模拟2002年7月30日在该地点发生的洪水事件。利用机载激光测高（LiDAR）和数字地图数据的结合，为每个模型构建了一个描述底层地形的相同数值网格，并用于运行基准模拟。然后进行了两个数值实验来测试每个模型对地形误差和摩擦参数化不确定性的响应。虽然所有测试的模型都产生了合理的结果，但特定代码组之间的细微差异为城市水力建模的实践和科学提供了相当大的见解。特别是，现代激光雷达系统提供的地形数据具有足够的精度和分辨率来模拟城市流量，但这些数据需要与建筑物拓扑和土地利用的数字地图数据融合，以最大限度地利用其中包含的信息。当这些地形数据可用时，对于典型问题，摩擦参数的不确定性成为比地形误差更重要的因素。模拟还表明，城市环境中的流动具有向超临界流动和数值激波的多次过渡的特征。然而，这些影响是局部的，它们似乎不会影响整个波的传播。相反，惯性项在这种特殊情况下是很重要的，但是试验场的特殊特征可能意味着这并不适用于更普遍的情况。
This paper describes benchmark testing of six two-dimensional (2D) hydraulic models (DIVAST, DIVAST-TVD, TUFLOW, JFLOW, TRENT and LISFLOOD-FP) in terms of their ability to simulate surface flows in a densely urbanised area. The models are applied to a 1.0 km x 0.4 km urban catchment within the city of Glasgow, Scotland, UK, and are used to simulate a flood event that occurred at this site on 30 July 2002. An identical numerical grid describing the underlying topography is constructed for each model, using a combination of airborne laser altimetry (LiDAR) fused with digital map data, and used to run a benchmark simulation. Two numerical experiments were then conducted to test the response of each model to topographic error and uncertainty over friction parameterisation. While all the models tested produce plausible results, subtle differences between particular groups of codes give considerable insight into both the practice and science of urban hydraulic modelling. In particular, the results show that the terrain data available from modern LiDAR systems are sufficiently accurate and resolved for simulating urban flows, but such data need to be fused with digital map data of building topology and land use to gain maximum benefit from the information contained therein. When such terrain data are available, uncertainty in friction parameters becomes a more dominant factor than topographic error for typical problems. The simulations also show that flows in urban environments are characterised by numerous transitions to supercritical flow and numerical shocks. However, the effects of these are localised and they do not appear to affect overall wave propagation. In contrast, inertia terms are shown to be important in this particular case, but the specific characteristics of the test site may mean that this does not hold more generally.