Flood Inundation Modelling for Mid‐Lower Brisbane Estuary

This study utilizes a two‐dimensional hydrodynamic model to calibrate and validate an inundation model for the Brisbane River estuary in Queensland, Australia. The bathymetry data used in the hydraulic model are derived from one arc second (1 s) shuttle radar topography mission digital elevation model, and the two‐dimensional hydraulic model is parameterized using the generated bathymetry with four open boundaries with water level observations and roughness coefficients. The calibration performance is evaluated by comparing the simulated results with the digitized records during the January 2013 flood event (a low magnitude event) at three gauging stations. The calibrated model is validated with water level data and available discharge data during the January 2011 flood (a large magnitude event) at four gauging stations located along the Brisbane River. Different performance indices are applied to demonstrate that the developed model performs well during calibration and validation. A sensitivity analysis is presented to assess the influence of riverbed elevation changes on the model because the main uncertainty of the model is the bathymetry data. The proposed model with the shuttle radar topography mission digital elevation model‐derived riverbed elevation for the Brisbane estuary is able to predict the flood inundation extent at an accuracy of 66.9% which is higher than or comparable with the accuracies of the existing studies. However, it is expected that the accuracy will increase if some improved bathymetry data become available in the future. Copyright © 2016 John Wiley & Sons, Ltd.     

西控工程对望虞河西岸地区防洪的影响

为了评估西控工程对望虞河西岸地区造成的防洪影响,以望虞河西岸为研究区域并结合其水文特性,构建了适合于模拟平原河网地区产汇流过程的MIKE11水文水力模型并利用当地降雨、水位等实测资料进行了率定。通过模拟50年一遇设计暴雨情况下的不同工况,得到研究区域内水系各节点的水位等要素变化情况,并依此分析了西控工程对望虞河西岸地区造成的防洪影响。结果表明:西控工程运行后,研究区域内重要节点的最高水位抬升明显,部分地区有遭受洪水淹没的风险;MIKE11水文水力模型对于分析平原河网地区河流沿线闸控影响具有较高的应用价值。     

茜坑水库溃坝洪水数值模拟研究

研究应用M IKE21模块建立茜坑水库溃坝洪水演进数学模型,模拟洪水演进过程。从最不利因素考虑,确定坝址处溃坝最大流量、洪水下游演进过程和下游淹没水深,为制定水库大坝安全管理应急预案提供技术支撑。     

Flow structure through pool‐riffle sequences and a conceptual model for their sustainability in gravel‐bed rivers

Detailed field measurements and simulations of three‐dimensional flow structure were used to develop a conceptual model to explain the sustainability of self‐formed pool‐riffle sequences in gravel‐bed rivers. The analysis was conducted at the Red River Wildlife Management Area in Idaho, USA, and enabled characterization of the flow structure through two consecutive pool‐riffle sequences, including: identification of jet concentration and dissipation zones, and the development of local turbulence features (i.e. vertical and horizontal eddies) under different flow conditions. Three‐dimensional hydraulic simulations were used to evaluate how the flow structure varies across a range of flow conditions and with different degrees of sediment aggradation within the upstream pool. The analysis demonstrated a significant influence of the residual pool depth on the flow structure, with reduced residual depth causing a shift in the orientation of the jet and a reduction in the influence of vertical eddies and the size and intensity of horizontal eddies. The proposed conceptual model seeks to explain the sustainability of pools in terms of the flow structure in pool‐riffle morphology and how this flow structure will change as a result of altered external forcing, such as upstream sediment delivery or changes in bank stability. Copyright © 2010 John Wiley & Sons, Ltd.     

基于MIKE FLOOD的城区溃坝洪水模拟研究

大坝安全不仅影响工程效益,还影响人民的生命和财产安全,溃坝洪水模拟可以对水库大坝的失事影响做出评估,对制定应急预案和防洪减灾具有重要意义。以深圳市龙华新区民治水库及下游片区为研究对象,基于MIKE FLOOD将MIKE11模型和MIKE21模型进行动态耦合,对溃坝洪水在下游的演进过程进行仿真模拟。模型采用瞬间溃(瞬间部分溃和瞬间全溃)以及逐渐溃两种溃决方式,分别模拟4种工况下的溃口流量过程线以及下游洪水演进过程。结果表明:瞬间溃的洪峰流量较大,出现在溃坝开始时刻,而逐渐溃的洪峰流量相对较小,出现在渗透破坏变形发展至上部坝体坍塌时刻,之后均随库区水位逐渐降低,下泄流量变小,直至库区水体排空。溃坝洪水对上游地区横岭村附近破坏较大,淹没水深较深。民治河中游段居民和商业区附近洪水流速接近5 m/s,对建筑物有一定破坏力,左侧向南村地势较低,淹没情况最为严重,并且在洪水消退后仍有3 m左右积水。民治河下游地区在洪水消退后也有少量积水。     

Evaluation of performance of Active,Beautiful and Clean (ABC) on stormwater runoff management using MIKE URBAN: a case study in a residential estate in Singapore

ABSTRACT

Singapore has adopted a low impact development equivalent of stormwater management philosophy under a national program called ‘Active, Beautiful and Clean’ (ABC) employing soft-engineering techniques to manage rainfall runoff in the face of climate change and rapid urbanisation. This study makes use of the MIKE URBAN modelling tool to evaluate the performance of ABC units in a new residential precinct based on flow data collected. Calibration results show an overall good fit between the measured data and simulated results based on three goodness-of-fit stats. The runoff factors computed for scenarios with and without the presence of ABC units show an improvement in the range of 21–72%. This study demonstrates the usefulness of using a calibrated model to evaluate the performance of constructed units using measurements. It is recommended that this modelling tool be also used for evaluating water quality performance of the units as well as applying it for use in the planning and implementation process.     

变化条件下河堤防洪能力复核分析研究

构建了一维河道洪水模型,基于历史洪水率定的河道糙率,模拟了发生设计标准洪水时河道中洪水演进过程,并采用不同方法推求的水面线校核了模拟结果的合理性,分析模拟了水位与确保水位及堤高数量关系,讨论了滩地糙率对洪水位的影响.实例结果表明,石佛寺水库下游河道个别断面堤不能满足设计标准洪水的过流要求,需进行堤防加高处理,滩地糙率对河道行洪水位影响较大.     

基于MIKE11的太子河观-葠河段水文水动力模型研究

针对辽宁省太子河观音阁水库至葠窝水库河段水环境污染严重的现状,采用MIKE11软件构建了流域水文水动力模型,以流域水量平衡和枯水期流量拟合效果佳为原则,利用长序列逐日气象水文实测资料进行了参数率定及模型检验,并分析了参数的敏感性和取值合理性.结果表明,模型在率定期和验证期模拟效果均良好,可供水质研究及库群与闸坝联合调度方案研究参考.     

Decision support systems in water resources in the demarcated region of Douro – case study in Pinhão river basin,Portugal

This paper puts forward the importance of decision support systems (DSS) for the planning and management of water resources. A case study of the Pinhão river basin, in Portugal, is presented. Given the importance of vineyards in the Douro region, it is important to determine if water availability will be enough to meet present and future water demands. In order to answer this question, DSS tools were used to assess different scenarios. The MIKE BASIN software was used in the hydrographical basin of Pinhão river, assisted by a geographic information system, GIS, which allowed the modelling of the basin, both temporally and spatially, facilitating the visualisation and interpretation of results. According to the attained results, it was verified that, at present, the hydrographical basin meets the considered water needs. The DSS proved to be an important tool to assist the decision‐making process in the studied river basin.     

长江口洪季水动力对海平面上升的响应特征

考虑到海平面上升对长江口水动力构成的严重威胁,该文基于MIKE21软件建立了长江口二维水动力数学模型,采用实测潮位、流速以及流向资料对模型进行了验证。对相关文献和IPCC报告进行总结归纳,得到2100年海平面保守上升值约为0.5 m。运用验证好的数学模型对海平面上升0.5 m后长江口洪季水动力进行了数值模拟。计算结果表明:海平面上升后,涨潮时间增长,落潮时间缩短;海平面上升0.5 m后,长江口南北支、南北港以及南北槽高潮位增加了0.43 m–0.46 m,高潮位增幅沿程向上减小,北支上段涨潮动力受阻较明显(潮位增幅较大);海平面上升0.5 m后,北支流速增幅比南支大,北支上段落潮流量增幅达82.8%,对北支水道的发展有利。总体而言,海平面上升对目前长江口沿岸的标准构成了一定威胁,但对已经衰退的北支水道有利。