(1.School of Energy and Power Engineering,Yangzhou University,Yangzhou,Jiangsu 225127,China;2.Science & Technology Commission of Water Resources Department of Jiangsu Province,Nanjing,Jiangsu 210029,China)
In order to know the evaporating capacity of channel and lake reservoir water surface along Jiangsu section of the Eastern Route of South-to-North Water Diversion Project(JERP),its power loss of the pumping stations and its influence on water transfer efficiency of JERP,evaporating capacity calculating models and formulae which are suitable for the areas where JERP locates were analyzed and compared.Evaporating capacity of every channel and lake reservoir water surface along JERP was calculated by integral.Both spacial and temporal distribution characteristics of the evaporating capacities of water surfacs were analyzed.The discharge loss and input power loss of every step pumping stations caused by water surface evaporation were calculated.The effect of water surface evaporation on water transfer efficiency of JERP was computed and analyzed.The results show that the evaporating capacities of water surfaces gradually increase from south to north and north- west,and are largest in summer and least in winter.The annual average evaporating capacity of water surfaces amounts to 862.2 mm.The evaporation water volume losses of Hongze Lake,Luoma Lake,Baima Lake and water transfer channels are 77.7%,13.3%,3.6% and 5.4% of the total evaporation water volume loss respectively.17.46% of the water pumped by source pumping stations loses for evaporation,which causes water transfer efficiency of JERP to decrease by 10.33%,and that is a considerable energy loss.Pipelines could be considered for the great water transfer projects which could avoid evaporating capacity of water surface.
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