本文選題：河網(wǎng) + 非恒定流��； 參考：《揚州大學(xué)》2017年碩士論文

【摘要】：為了改善河流水環(huán)境,嘉興市依托海綿城市建設(shè),借助“引清濟污”的調(diào)水手段來提升河道自凈能力,加快河道的治理速度�；诂F(xiàn)有工程設(shè)施,研究河流水動力條件,優(yōu)化引排活水調(diào)度方案,對生產(chǎn)實踐具有重要的意義。本文采用Saint-Venant方程組,建立了河網(wǎng)非恒定流數(shù)學(xué)模型,運用Preissmann四點加權(quán)隱格式,對方程組進行時間和空間離散,采用雙松弛迭代法求解河網(wǎng)非恒定流。利用Sen和Garg提出的環(huán)狀河網(wǎng)和Islam等人提出的拓撲型河網(wǎng)這兩個算例對本文計算方法進行驗證。在環(huán)狀河網(wǎng)計算中,本文方法計算得出的各斷面流量過程與Sen和Garg計算的各斷面流量過程基本吻合。各斷面流量過程線的計算峰值和文獻中流量過程線峰值相對誤差最大達到-2.67%。在拓撲型河網(wǎng)計算中,本文方法計算所得的流量過程和水位過程與Islam等人計算的基本吻合。各斷面流量過程線的峰值和文獻中流量過程線峰值相對誤差最大達到1.17%,水位過程線的峰值和文獻中水位過程線峰值絕對誤差最大為-0.02m。計算研究表明:本文所提河網(wǎng)數(shù)學(xué)模型及計算方法具有模擬復(fù)雜河網(wǎng)明渠水流運動的能力。本文對兩種泵站抽排方案,觀測了嘉興市區(qū)12個典型斷面的水位值,并利用觀測的水位值對河網(wǎng)河道糙率進行了率定。率定后的河網(wǎng)模型在典型斷面處的計算水位值和實際測量值的絕對誤差基本在±0.05m以內(nèi),表明所建立的模型適用于所選定的區(qū)域且具有較高的精度。利用上述已經(jīng)率定的嘉興市區(qū)河網(wǎng)非恒定流數(shù)學(xué)模型,對低水位、常水位、高水位三種工況共57種方案進行數(shù)值模擬,以河網(wǎng)平均流速、滯水率、南湖入流量、重點河道平均流速作為優(yōu)化指標,對三種工況下的外部方案、內(nèi)外部結(jié)合方案、規(guī)劃方案進行分析,并分別獲得了泵站引排活水優(yōu)化方案。
[Abstract]:In order to improve the river water environment, Jiaxing relies on the construction of spongy city, by means of the water transfer means of "leading away the pollution" to improve the self-purification ability of the river and speed up the river course management. Based on the existing engineering facilities, it is of great significance for production practice to study the hydrodynamic conditions of rivers and optimize the scheduling scheme of diversion and drainage. In this paper, the mathematical model of unsteady flow in river network is established by using Saint-Venant equations. The equations are discretized in time and space by using Preissmann four-point weighted implicit scheme, and the unsteady flow of river network is solved by double relaxation iterative method. The calculation method of this paper is verified by two examples proposed by Sen and Garg and topological river network proposed by Islam et al. In the calculation of annular river network, the flow process of each section calculated by this method is basically consistent with that calculated by Sen and Garg. The maximum relative error between the calculated peak value of flow process line of each section and the peak value of flow process line in literature is -2.67. In the calculation of topological river network, the flow process and water level process calculated by this method are in good agreement with those calculated by Islam et al. The maximum relative error between the peak value of flow process line of each section and the peak value of flow process line in literature is 1.17, and the absolute error of water level process line and water level process line in literature is -0.02 m. The calculation results show that the mathematical model and calculation method proposed in this paper have the ability to simulate the flow movement of open channel in complex river network. In this paper, the water level values of 12 typical sections in Jiaxing urban area are observed for two pumping station drainage schemes, and the roughness of river network is determined by using the observed water level values. The absolute error between the calculated water level at the typical section and the actual measured value is within 鹵0.05 m, which indicates that the established model is suitable for the selected area and has a high accuracy. Using the mathematical model of unsteady flow in Jiaxing urban area, 57 schemes of low water level, constant water level and high water level are numerically simulated. The average velocity of the key river channel as the optimization index, the external scheme, the internal and external combination scheme, the planning scheme under three working conditions are analyzed, and the optimal scheme of pumping station diversion and drainage is obtained respectively.
【學(xué)位授予單位】：揚州大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TV213.4
，

本文編號：1988953