Experimental Study On Hydraulic Characteristics Of Pumping Well Water To Melt Ice For Diversion Channel In Cold Region

In the northwest of the cold region, it can easily cause the ice harm because of the low temperatures and small river flow. These phenomena are not only having an impact on the effectiveness of the work of diversion hydropower station, but also bringing huge economic losses and safety hazards. Thus, controlling the ice in diversion channel is the key issue of diversion type hydropower must be considered. In the existing prevention measures, it is the best measures to solve these problems by injecting the groundwater with higher water temperature into the lower water temperature in channel to increase the water temperature. In this process, not only can it prevent the generation of ice, but also it can increase the flow channels for power generation. Recently there are few researches largely concentrated in the water within the ice formation and evolution, instead of the corresponding experimental study rarely involved. However,with the pumping method for controlling channels ice has application and achieved good results. In this paper, we went to Xinjiang Hongshanzui Hydropower and got some experience about melting ice diversion channels, by the observation and model test, we found that the valid data measured get the temperature variation along the diversion channels and the influence of antifreeze length with single well.We did the test in different situations. There are four situations with no well, single well, double wells,and three wells, and performed on 4 different groups of canal water flow and 3 groups of different water flows. Then at four different positions it would do the single well test. Next at six different position combinations it would do the double wells test. Finally, at four different position combinations it would do the three wells test. Through the test it can analyze some rules about them and combined with the experimental results obtained corresponding formula. When there is no well, water temperature decreases regular, and to compare with the theoretical formula and experimental values, so it is found that the formula fitted better; and based on these, also studied about single well, double wells and three wells tests, found the rules and formulas, too. They do fitting better, the maximum errors are only 9.7%, 9.82%, and 9.75%,that makes them can calculate the canal water temperature in different canal water flows, well flows and different positions.For the influence of antifreeze length is from different hydro, thermal and climatic conditions. There were three different sets of canal water flow and three different sets of well water flow. The results showed that: If the hydraulic conditions changed, the smaller they change, the faster the ice density growth, it can rapid from 0% to 4.5%, and the flow rate was 0.0843m/s, the shorter antifreeze length is. On the contrary,the ice density is maintained at a distance of 0% to 1.6% after the increase, the flow rate change width was0.0646m/s, the longer antifreeze length is; If only thermal conditions or weather conditions changed, the smaller they change, the shorter the length is. On the contrary, the larger they change, the longer the ice-free is; on this basis, we got their relationship and established a quantitative formula. Also the experimental results can provide scientific basis for pumping melting operation mechanism and provide reference for practical engineering.