面向藏木电站下闸蓄水日期选择的雅江中游径流预测研究

发布时间：2018-01-26 13:40

  本文关键词： 雅鲁藏布江中游 径流趋势分析 水文模型 径流预测　出处：《清华大学》2014年硕士论文　论文类型：学位论文

【摘要】：雅鲁藏布江(以下简称雅江)是西藏地区最大的河流,亦是世界上海拔高度最高的大河,境内流域面积大约24万km2,水能蕴藏量巨大。根据第五次西藏工作座谈会提出的要将西藏建设成为国家重要的能源接续基地的目标要求,雅江流域的水能资源开发将成为我国水电工程建设的重点区域之一。目前,雅鲁藏布江中游羊村水文站以下至加查峡谷段规划了巴玉、大古、街需、藏木、加查、冷达、仲达等7个梯级电站。其中,藏木水电站已于2010年开工建设,是雅江干流的首座水电站,也是西藏境内目前在建的最大规模的水电站,总装机容量为51万kw。按照藏木水电站2014年10月底至11月上旬首台机组发电的工程建设目标,电站计划2014年10月份择机下闸蓄水,设计工况为Q=839m3/s下第六扇导流底孔封堵闸门开始蓄水。为合理选择藏木水电站下闸蓄水日期,同时也为水电站日后运行需要,对雅鲁藏布江中游河段藏木断面(羊村站)的径流模拟和预测分析十分必要。在文献调研和实测资料收集的基础上,本文基于羊村站1956-2003年的月实测平均流量数据,利用MK法进行的雅江中游水文变化的检验分析。分析结果表明,1956-2003年,雅江干流径流有增加的趋势,但统计量未通过显著性检验,说明趋势性变化不明显;根据MK突变检验显示,雅江中游1969年之后UF值开始明显下降,1997年之后UF值开始明显上升,相应的累计距平法检验也发现突变年份发生在1959年、1964年、1987年和1997年,其中1997年绝对值最大。为预测径流,本文采用了三个水文模型对雅江中游流域的径流进行模拟,包括三水源XAJ、SIMHYD模型和SMAR模型;对水文模型进行参数优化时使用SCE-UA算法。结果表明,三种模型模拟精度差别不大,以R2评价,XAJ模型的精度最高,其次为SIMHYD模型,SMAR模拟精度最低;以RE评价,XAJ模型模拟结果与实测流量的误差最小,精度最高,SMAR次之,SIMHYD模型模拟结果稍差。最后,利用率定好的三种模型进行径流预测,并针对藏木水电站10月下旬下闸蓄水的设计流量值,给出了各自的推荐方案。雅江地势高耸,人烟稀少,水文资料极度缺乏。本文利用有限的实测资料结合数学方法和水文模型开展雅江径流变化分析及预测,将有丰富相关区域的水文水资源研究,为区域经济发展和生态保护提供积累。
[Abstract]:The Brahmaputra River (hereinafter referred to as the Yajiang River) is the largest river in Tibet and the highest elevation river in the world, with an area of about 240,000 km2. The water and energy reserves are huge. According to the 5th Tibet work Symposium, the goal of building Tibet into an important energy base for the country is required. The exploitation of water and energy resources in the Ya River Basin will become one of the key areas in the construction of hydropower projects in China. At present, the section from Yangcun Hydrological Station in the middle reaches of the Yarlung Zangbo River to the Gacha Gorge has been planned for Bayu, Dagu, Street needs and Tibetan Wood. Among them, the Zangmu Hydropower Station, which began construction in 2010, is the first hydropower station in the main stream of the Yajiang River and the largest hydropower station under construction in Tibet. The total installed capacity is 510,000 kw. according to the construction target of the first generating unit of Zangmu Hydropower Station from the end of October 2014 to early November, the power station plans to select the machine to lower the sluice to store water on October 2014. The design conditions are as follows: 6th sluice gates under QT 839m3 / s for sealing and plugging the sluice gate. In order to reasonably select the storage date of the lower gate of Zangmu Hydropower Station, it is also necessary for the future operation of the hydropower station. It is necessary to simulate and forecast the runoff of the Tibetan wood section (Yangcun station) in the middle reaches of the Yalu Zangbo River. Based on the monthly measured average discharge data of Yangcun Station from 1956 to 2003, this paper uses MK method to test and analyze the hydrological changes in the middle reaches of the Yajiang River. There is an increasing trend in the runoff of the main stream of the Yajiang River, but the statistical quantity does not pass the significance test, which shows that the trend change is not obvious. According to the MK mutation test, the UF value began to decrease obviously after 1969 in the middle reaches of Yajiang River, and the UF value began to increase obviously after 1997. The corresponding accumulative anomaly test also found that the mutation year occurred in 1959, 1964, 1987 and 1987, in which #date鈪，

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