摘要
南水北调中线工程自2014年12月全线通水以来已运行8个冬季,为防止冰塞冬季输水流量控制为设计流量的30%~50%,严重制约了工程输水效益的发挥。因此,渠道水温和冰盖特性一直是冬季输水关注的重点问题之一。实测数据表明:①冬季输水流量总体逐年增大,最末段保持相对稳定,岗头闸流量约为50 m^(3)s,北拒马河闸约为25 m^(3)s;②冬季气温总体以暖冬居多。保定站最低气温-22.0℃,3日滑动气温极值-10.7℃,短期强寒潮可能是今后冰盖生成的关键驱动因子;③冬季水温沿程逐渐降低,渠首陶岔闸最低水温6.7℃,渠末北拒马河闸多数年份降至0℃附近。北拒马河闸水温最大降幅10日内由3.5℃降至0℃,期间渠段水温降幅亦达到极大值1.69℃100 km。④2016年冬季冰盖最长达280 km(最南端延伸至午河闸),次之为2015年冬季的73 km和2021年冬季的38 km,有两个冬季未生成冰盖。岗头闸-北拒马河闸近90 km是冰盖多发渠段,应引起关注。基于冰盖生成前实测数据,以初始水温和区间气温为输水条件,拟合给出了2 d、3 d和7 d等不同预报时效的简化水温模型和冰盖生成临界阈值。初步分析认为:冬季气温和输水流量是冰盖生成的两大关键驱动因子,流量越小气温越低越易生成冰盖,1月出现的短期强寒潮更易于导致冰盖生成。2016年冬季严重冰情是二者叠加的结果,2015年冬季冰盖主要是输水流量小诱发,而2021年冬季冰盖主要是短期强寒潮所致。
The middle route of South-to-North Water Diversion Project has been in operation for 8 winters since its full operation in December 2014,and the water conveyance flow is controlled to 30%-50%of the design flow during the ice period in order to prevent the ice jam disaster,which seriously restricts the water conveyance benefits of the project.Therefore,the channel water temperature and ice cover have been one of the key issues in winter water conveyance.Field measurement data shows that①Winter water conveyance flow generally increased year by year,and the end canal section remained relatively stable,the flow rate of Gangtou sluice was about 50 m^(3)s,that of Beijumahe sluice was about 25 m^(3)s;②Winter temperatures have generally been mostly warm.The minimum temperature at Baoding station was-22.0℃,and the 3 d moving temperature pole was-10.7℃.A short-term strong cold snap may be a common pattern for future ice cover generation;③In winter,the water temperature decreases gradually along the range,with the lowest water temperature at the head of the drain Taocha sluice being 6.7℃,and at the end of the canal Beijumahe sluice falling to around 0℃in most years.The maximum drop of water temperature in the Beijumahe sluice was from^(3).5℃to 0℃in 10 d,and in the canal section reached 1.7℃100 km during the period;④The longest ice cover was 280 km in winter 2016,followed by 73 km in winter 2015 and 38 km in winter 2021,and no ice cover was generated in winter 2020 and 2022.Nearly 90 km of Gangtou sluice to Beijumahe sluices is the section with frequent ice cover,which should be a concern.Based on the measured data before ice cover generation,the initial water temperature and interval air temperature model is used to fit the concise water temperature prediction model and the critical threshold of ice cover formation with different forecast timeliness of 2 d,3 d and 7 d.The preliminary analysis concludes that:winter temperature and water flow are the two main drivers of ice cover generation,the lower the flow the lower the temperature the easier it is to generate ice cover,and the short-term strong cold wave in January is more conducive to ice cover generation.The severe ice regime in winter 2016 was the result of a combination of two factors;the winter 2015 ice cover was mainly induced by low water delivery flows,while the winter 2021 ice cover is mainly due to a short-term strong cold snap.
作者
段文刚
郝泽嘉
杨金波
黄明海
刘备
邢梦媛
DUAN Wengang;HAO Zejia;YANG Jinbo;HUANG Minghai;LIU Bei;XING Mengyuan(Changjiang River Scientific Research Institute,Wuhan 430010,China;China South-to-North Water Transfer Group Middle Line Co.,Ltd.,Beijing 100038,China)
出处
《水利学报》
EI
CSCD
北大核心
2023年第9期1025-1037,共13页
Journal of Hydraulic Engineering
基金
国家重点研发计划项目(2017YFC0405000)。
关键词
南水北调中线工程
冬季水温
冰盖
强寒潮
冰盖生成阈值
Middle Route of South-to-North Water Diversion Project
winter water temperature
ice cover
strong cold wave
ice cover formation threshold
