摘要
Abstract
On the premise of ensuring the safety of water delivery in winter,it is an important measure to adopt non-ice-covered large discharge water delivery mode to enhance the main canal water conveyance capacity of the South-to-North Water Transfers Project in winter,the thermal insulation of canal water conveyance is one of the key technical bottlenecks to ensure the operation of non-ice-covered water conveyance of main canal.
Based on the analysis of the water temperature and ice condition in the 8 winters since the water supply of the whole line under the current regulation of the Middle Route project,the operation method of non-ice-covered large-flow water conveyance is put forward to realize water conveyance and heat preservation in winter,aiming at four kinds of dispatching operation schemes of different water flow,such as 350,280,210 and 150 m3/s,simulation analysis of each scheme of water transfer in strong cold winter,cold winter,flat winter and warm winter weather conditions such as the winter heat preservation effect of the main canal.On this basis,a proposal for optimal operation of non-ice-covered water conveyance and thermal insulation of main canal in winter is proposed.
The results of numerical simulation show that:according to different typical winter weather conditions,the non-ice-covered large-flow water transfer operation mode is adopted under limited conditions,it can shorten the flow time of water conveyance and reduce the heat loss of water body,thus achieving the effect of heat preservation,the water temperature at the end of the open channel is also higher than that at the end of the open channel,at the same time,it can also effectively solve the problem of limited water conveyance capacity in winter.
Based on the short-term air temperature forecast and water temperature forecast in the main canal,it is suggested that water transfer operation mode with larger water discharge should be adopted as far as possible under the typical winter weather conditions such as cold winter,flat winter and warm winter,and under the strong cold winter weather conditions,non-ice-cap large flow water conveyance model can be used in time and channel sections.关键词
南水北调中线工程/无冰盖输水/大流量/保温措施/数值模拟Key words
Middle Route of South-to-North Water Transfers Project/water delivery without ice covered/large discharge/thermal insulation measure/numerical simulation分类
建筑与水利
