Numerical Simulation Of Wind Field Characteristics And Windbreak Measures In Construction Area Of Baihetan Hydropower Station

Baihetan Hydropower Station dam project is located in dry and hot valley, dry season(January to May, November to December) windy weather frequent. Dam construction process by the valley winds greater impact, more than seven winds will affect the operation of cable cranes and concrete pouring in the process of taking and feeding, while wind climate will cause serious impact on the safety, quality and schedule of concrete construction. Therefore, it is very important to study the distribution law of the wind field in the dam construction area and put forward the specific windbreak measures accordingly. It is of great significance to ensure the smooth construction, as scheduled, high quality and safe completion of the dam pouring task.In this paper, the numerical simulation of wind environment in the site of the dam site is carried out by using the fluid dynamics software FLUENT, which is based on Baihetan hydropower station in Jinsha River, The main contents are as follows:(1) Based on the terrain elevation data of the project, the reasonable calculation domain is set up, the three-dimensional digital model of the canyon terrain is established and divide the grid and grid are used unstructured grid. Using the Realizable k-? turbulence model, set reasonable boundary conditions. Firstly, the numerical simulation of a simple wind tunnel model is carried out to verify the feasibility of numerical simulation of such terrain.(2) Five kinds of working conditions of 600m, 650m, 700m, 750m and 800m on the crest elevation were calculated by numerical simulation, analysis wind field distribution of dam area,high and low line feeding platform and cable machine area and changes with the height of the dam. It is found that the working face of the dam construction area is maintained at a large wind level in the 9 stage of wind flow and it is difficult to meet the construction requirements.Based on the analysis of the numerical results of wind field in the dam area, two kinds of wind prevention measures are proposed, which are local windbreak measures and full face wind prevention measures.(3) To these two kinds of precautions to simulation, analysis wind field variation of different high dam crest area, high and low line reclaimer platform and cable machine area. It is found that the local windbreak measures can form more effective protection to the working face before the crest elevation rises to 700m, but its effect is basically lost at the high dam. The full face wind protection measures can form effective protection for each working face, but the existence of the wind channel will lead to large wind force in the stilling basin, in addition,there will be a large wind gradient in the cable area.By analyzing the advantages and disadvantages of the two kinds of wind protection measures, it is suggested that the local windbreak measures can be adopted when the dam height is low. With the increase of the dam body, The full face wind protection measures can be adopted when the local windbreak network can not meet the requirements of the dam construction.