水库分期旱限水位及抗旱调度研究

发布时间：2019-06-05 06:17

【摘要】：干旱一直是困扰人类的重大难题,尤其是西北地区干旱情况愈发严重。随着干旱情况日益突出,水库在抗旱研究中的作用越来越凸显,水库的合理调度运行在抗旱减灾中具有重要意义。本文致力于渭河流域冯家山水库的抗旱调度研究,旨在通过水库调节来缓解流域旱情。研究方法与主要成果如下:(1)以气象、水文指标为基础构建冯家山水库综合干旱指标,采用熵权法与模糊综合评价法计算灌区长系列综合干旱指数CDI,并依据区域干旱等级标准评价灌区干旱等级,分析冯家山水库干旱特征,结果表明:库区干旱程度整体呈缓慢增加趋势;90年代干旱次数迅速增多,是旱情最为严峻的时期;干旱最严重的时段为1986、1995和1997年;灌区干旱主要集中在春、秋两季。(2)建立缺水量最小的冯家山水库优化调度模型,采用动态规划法求解出水库运行过程,选择多年月平均降水、水库多年月平均入流及月平均水位三个指标作为样本值,利用专家评判法确定各样本因子的权重系数,采用Fisher最优分割法确定水库干旱分期,确定划分为4个分期:1月～3月,4月～6月,7月～10月,11月～12月。结合干旱等级与优化的水库水位结果确定各分期不同干旱等级对应的旱限水位。(3)先利用适线法确定冯家山水库的典型年,在水库优化调度的基础上考虑分期旱限水位,建立应对干旱的冯家山水库抗旱调度模型,采用动态规划法求解模型,从缺水量(长系列、典型年、连续枯水年)和供水保证率的角度对抗旱调度前后的结果进行对比分析,结果表明:缺水集中发生在90年代,抗旱调度前后长系列平均缺水率分别为3.35%、2.69%,抗旱后比抗旱前减小了 0.66%;特枯水年、偏枯水年抗旱调度后的缺水率分别比抗旱前减小了 2.91%、10.86%,平水年减小了 923万m3;抗旱调度前后偏丰水年与特丰水年均不缺水;抗旱调度后连续枯水年平均缺水率比抗旱前减小了 2.77%;抗旱调度后的年保证率高于抗旱前,生活、农业用水保证率分别增加了 2.3%、4.5%,生产、生态用水保证率不变。
[Abstract]:Drought has always been a major problem perplexing human beings, especially the drought situation in northwest China is becoming more and more serious. With the increasingly prominent drought situation, the role of reservoirs in drought resistance research is becoming more and more prominent, and the reasonable operation of reservoirs is of great significance in drought resistance and disaster reduction. This paper is devoted to the study of drought resistance operation of Fengjiashan Reservoir in Weihe River Basin, in order to alleviate the drought situation of Fengjiashan Reservoir through reservoir regulation. The research methods and main results are as follows: (1) based on meteorological and hydrological indexes, the comprehensive drought index of Fengjiashan Reservoir is constructed, and the long series comprehensive drought index CDI, of irrigation district is calculated by entropy weight method and fuzzy comprehensive evaluation method. According to the regional drought grade standard, the drought grade of irrigation area is evaluated, and the drought characteristics of Fengjiashan Reservoir are analyzed. the results show that the drought degree of Fengjiashan Reservoir area as a whole tends to increase slowly. In the 1990s, the number of droughts increased rapidly, which was the most severe period of drought, the worst period of drought was 1986, 1995 and 1997, and the worst period of drought was 1986, 1995 and 1997. The drought in irrigation area is mainly concentrated in spring and autumn. (2) the optimal operation model of Fengjiashan Reservoir with the least water shortage is established, the operation process of the reservoir is solved by dynamic programming method, and the monthly average precipitation is selected for many years. Three indexes of monthly average inflow and monthly average water level of reservoir are used as sample values. The weight coefficient of each sample factor is determined by expert evaluation method, and the drought stage of reservoir is determined by Fisher optimal segmentation method. It was divided into four stages: January to March, April to June, July to October, November to December. Combined with the results of drought grade and optimized reservoir water level, the drought limit water level corresponding to different drought grades in each stage is determined. (3) the typical year of Fengjiashan Reservoir is determined by the method of suitability, and the stage drought limit water level is considered on the basis of reservoir optimal operation. The drought resistance operation model of Fengjiashan Reservoir is established, and the model is solved by dynamic programming method. The results before and after drought resistance operation are compared and analyzed from the point of view of water shortage (long series, typical years, continuous dry years) and water supply guarantee rate. The results showed that the water shortage occurred in the 1990s, and the average water shortage rate of the long series before and after drought resistance dispatching was 3.35% and 2.69% respectively, which decreased by 0.66% after drought resistance compared with that before drought resistance. In the special dry year, the water shortage rate after drought resistance regulation in the dry year is 2.91%, 10.86% and 9.23 million m ~ 3 lower than that before drought resistance, respectively, and there is no water shortage in the high water year and the special water year before and after drought resistance dispatching, and the water shortage rate in the low water year is 2.91% and 10.86% respectively, and that in the flat water year is 9.23 million m ~ 3, respectively. The average annual water shortage rate of continuous dry water after drought resistance dispatching was 2.77% lower than that before drought resistance. The annual guarantee rate after drought resistance dispatching was higher than that before drought resistance. The guarantee rate of daily and agricultural water use increased by 2.3% and 4.5% respectively. The guarantee rate of production and ecological water use remained unchanged.
【学位授予单位】：西安理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV697.1

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