Study On The Effects Of Surrounding Areas Outdoor Thermal And Humid Environment Of Three Gorges Reservoir

The Three Gorges Reservoir is the biggest project of irrigation works hinge in the world. As 7 years of construction from 2003 to 2009, the Three Gorges Dam project has become a huge artificial lake with the capacity of 39.3 billion cubic meters and a total area of 1084 square kilometers which includes 21 countries and towns of Chongqing and Hubei. The Three Gorges Reservoir involves hundreds of kilometers along the coast of residential environment. Especially after the completion of the reservoir, the rise of water lever changed the flow of the water itself, the water surface has expanded and the water velocity slows down, thus the thickness of “air-water” boundary layer and the heat transfer between the river and environment was also affected. On the other hand, due to the sharp expansion of the water surface, the change of the original underlying surface caused the change of local regional climate through the surface roughness and reflectivity, and finally affected the overall climate of the reservoir. Large capacity of heat storage of the water makes its powerful ability of thermoregulation, city water body acts a significant role at the aspect of improving residential environment. Therefore, based on the previous study, this paper will study on the following aspects that focus on the effects of surrounding areas thermal and humid environment after the Three Gorges Reservoir:Firstly, in order to analyze the effects of surrounding areas thermal and humid environment influenced by water body, the “counting sheep theory” is proposed and then constitutes the research foundation combined with the heat transfer mechanism in the “air-water” interface. Meanwhile, the Yangtze River and Jialing River was chosen as the study objects to analyze the heat and moisture transfer based on the “air-water” interface in a test cycle of 24 hours. The results of the test data show that the cooling effect value increased with the change of seasons and the rise of air temperature. The range of cooling effect value is 1889.4?15752.8KJ/m2? d during all the period of tests. Compared with concrete underlying surface, the expansion of water surface results in the decrease of air temperature in the original area; Compared with soil underlying surface, the expansion of water surface results a slight increase of air temperature. Besides, in terms of the moisture transfer, the water vapor always sent from water surface toward air and the water body always has wet effects to surrounding environment within the range of 10.2?322.6 g/m2? d.Secondly, the thermal and humid influence model of surrounding areas influenced by city water body is established to analyze the variation of heat and moisture transfer of coast water body based on the per unit area heat and moisture transfer amount and the overall water area of Chongqing main city. The test results show that the thermal effect of coast area influenced by water body is the lowest in winter and the highest in summer. The range of temperature effects during all the period of tests within the scope of 2.5km and 5km are 0.08?0.64? and 0.04?0.36? respectively; Besides, the range of the effects of air specific humidity influenced by water body within the scope of 2.5km and 5km are 0.0007?0.021g/kg and 0.0004?0.012g/kg respectively.Lastly, beyond the existing heat and moisture test, this research also used mobile measurement to analyze the scope of thermal and humid influence in the vertical direction of the coastal area aimed at the typical measuring point in the middle and lower reaches of Three Gorges Reservoir. The test results show that water body has the cooling and wetting effect on the surrounding air in summer. In the vertical direction of the river, the direction of heat transfer is toward the water body and the direction of moisture transfer is deviate from the water body within a certain scope. Among all the 6 tests in this survey, the range of temperature reduce rate of coastal area influenced by water body within a certain scope is 0.16?0.45?/100 m and the range of moisture growth rate is 0.43%?1.91%/100 m. Besides, the analysis of the scope of thermal and humid effect in the vertical direction shows that, the thermal and humid effect of coastal area is mainly influenced by the air thermal motion. When the air temperature is higher, the water body can affect a wider scope through more severe air thermal motion.