【作者】 李俊娜；

【导师】 张绪进； 文岑； 缪吉伦；

【作者基本信息】 重庆交通大学 ， 港口、海岸及近海工程， 2008， 硕士

【摘要】 一维水沙数学模型已在防洪、航运及水库泥沙等工程领域得到了广泛的应用。由于河床演变的不确定性,航道整治的复杂多变性以及目前数值模拟技术的广阔应用前景。本文在系统分析泥沙数学模型的发展历史和研究现状的基础上,依托西部交通建设科技项目——西江干线梧州~郁南航道工程关键技术研究课题,结合西江推移质输沙水槽试验,建立了一维非恒定水流模型和非耦合水沙数学模型,模拟梧郁段洪水演进过程,定性分析了潮汐、长洲枢纽运行对下游航道的影响,并研究了该河段在天然情况与清水下泄情况下泥沙冲淤的时间和空间分配。具体研究内容包括六章:第一章为绪论,较系统地阐述了一维水沙数学模型的研究现状、存在的主要技术难点及数值计算方法,在此基础上结合实际工程应用提出了本文的研究内容。第二章概述西江整治河段的情况,利用现有资料进行定性的河床演变分析,揭示了浅滩形成的内在原因,就整治思路及方案进行了探讨,并就整治高度、宽度进行了初步的计算分析。第三章采用线性化Preissmann格式,以Z、Q为因变量对圣维南方程组进行离散,建立适用的非恒定水流模型,在验证计算的基础上,针对西江进行了洪水、潮汐及日调节非恒定流计算,分析了非恒定流在西江梧州~肇庆段传播规律及其为四滩整治方案确定提供了科学依据。第四章结合水槽试验及水文资料建立了适合研究河段的推移质输沙率公式及流量水位关系式,确定了计算采用的泥沙起动流速公式、悬浮指标半经验计算模式,建立了全河段的全沙模型。第五章在验证基础上进行长河段的泥沙冲淤计算,结果表明,长洲枢纽建成后,清水下泄将导致梧州~界首段发生冲刷,而界首~三滩段将发生淤积。对整治后三滩河段航道维护不利。同时,利用SMS计算了近坝段河床冲淤变化情况,分析其对航道条件的影响。第六章结论与展望,对本文工作进行了总结并对今后的研究应用前景进行展望,指出了今后的研究方向。更多还原

【Abstract】 It is based on the systematic analysis of the developing history and the present situation of the sediment mathematical model in this paper.It is dependent on West transportation Science and Technology Project—Study on Xijiang River between Wuzhou andYunan waterway project key technology, and developed a 1-D mathematical flood routing model for unsteady flow and total sediment model. The model will simulate the flood evolution, qualitative analysis tide, key position to the downstream route influence, and the silt’s space and time distribution in the different situation.There are six chapters, as follows:Chap 1: The present research situation, the numerical scheme of the 1-D flow and sediment model are concluded, and the main work of the paper is put forward.Chap 2: Outlines of the situation of Xijiang-River, the existence information is adopted to carry on the qualitative fluvial process. The intrinsic reason of shoal forms is revelated, and the improvement thought is proposed. The navigationable depth and the improvement-line width are determined.Chap 3: A new mathematical unsteady flow model is established, which based on the linear Preissmann scheme, with the variables of Q and Z. The flood evolution, the unsteady flow, the tide, the level and width are simulated.Chap 4: Based on the experiment, with current form Strength Index, deduced Sediment transport rate formula. Also on the basis of Professor Wang formula (Xi’an University of Technology) established the resumption of saturated coefficients formula.The experiment and hydrological data is adopted to process key questions, then the total sediment mathematical model is established.Chap 5: Based on Model confirmation, the different operating silt mode are calculated,and calculates the silt change in downstream by SMS. Then qualitative influence one channel condition is analysed.Finally, Sums up the whole paper and further research work is prospected.更多还原