Please use this identifier to cite or link to this item:
Flood stage prediction using Muskingum-Cunge method and rating curve
|Authors: ||Yu-Hsun Liao|
|Contributors: ||NTOU:Department of Harbor and River Engineering|
Muskingum-Cunge method;flood stage;loop rating curve
|Issue Date: ||2011-06-30T07:37:48Z
|Abstract: ||一般傳統降雨逕流模式僅適用於中型集水區之水文演算，如應用於大型集水區時，則因渠道貯蓄效應逐漸重要，會導致逕流演算誤差。貯蓄效應為水體質量暫時蓄積於渠道內之現象，或稱為逕流擴散現象，此將導致流量歷線尖峰有消減之趨勢。本研究利用馬斯金更-康鉅法進行渠道演算，以模擬洪水波運移過程之貯蓄效應與傳遞效應，且可避免動力波模式數值不穩定的問題。 研究中利用數值高程模式劃分欲計算渠道上游集水區、渠道兩側次集水區與殘流域之地文因子，而後採用地形性水文模式與馬斯金更-康鉅法進行逕流計算。因考量防洪預警過程需要渠道水位資料，故採用HEC-RAS軟體求得水位-流量率定曲線，而後利用Jones 公式以考慮率定曲線之遲滯現象，冀能確實反應洪水波運移時之水位變化。|
Conventional rainfall-runoff models can only be applied to midsize watersheds for runoff simulation. They cannot be applied to large watersheds because of the channel storage effect getting significant in large watersheds, which will induce large simulating error in flood routing. Channel storage effect results from water temporally stored in channel reaches, which is also recognized as the runoff diffusion to describe the phenomena of flow peak attenuation while flood wave transporting to downstream. In this study, Muskingum-Cunge method is adopted to perform the channel-flow routing to include translation and storage effects in flood wave transport and to avoid numerical instability problems while using a dynamic-wave model. A digital elevation model (DEM) was adopted to delineate lateral areas and the boundaries of subwatersheds along the mainstream. Detail geomorphic factors for the lateral areas and subwatersheds were calculated by using the DEM. Consequently, the geomorphic factors were as the input to a geomorphology-based runoff model to generate flow hydrographs to be the boundary conditions for the channel-flow routing using the Muskingum-Cunge method. Since flood stage information is usually required in flood warning systems, stage-discharge rating curves were derived using the HEC-RAS software. The hysteresis effect in the rating curve was further included by applying the Jones formula to have a more precise predicting in the channel-flow routing.
|Appears in Collections:||[河海工程學系] 博碩士論文|
Files in This Item:
All items in NTOUR are protected by copyright, with all rights reserved.