摘要
为了研究山区大风环境对大坝施工的影响并评价局部防风措施的防治效果,文章以山区水电站枢纽为研究对象,应用流体力学软件FLUENT对坝区包括坝体、上下游围堰及坝址区远场的范围进行了风场数值模拟分析。通过对不同坝高工况和不同防风率工况的对比分析,得到了大风条件下大坝周围的风场绕流情况,探讨了随着大坝浇筑高程的不断增长,大风经过大坝时风场分布的变化情况,最终确定了最优挡风率。研究结果表明:在坝区下游围堰上设置20m高防风网后,进入基坑内的气流减少,且气流显著上挑,坝顶上方的低速风区高度有显著的增大,形成有利于施工的安全区域。另外由于挡风作用,基坑底部存在回流,且低坝时基坑内流动不很稳定,流场较乱,导致坝顶高程620m以下时的风场结构较复杂。防风网方案在坝升高至680m前,可以对各工作面形成较为有效的防护,其防风网的最优挡风率为0.5-0.67。
In order to study the influence of mountainous wind environment on dam construction and evaluate the prevention and control effect of local windproof measures, this paper takes mountain hydropower station as the research object and applies fluid mechanics software FLUENT to the dam area including dam body, upstream and downstream cofferdams and the far field of the dam site to get numerical simulation analysis of the wind field. Through the comparative analysis of different dam height conditions and different windproof rate conditions, the wind field flow around the dam under strong wind conditions is obtained. With the increasing of the dam pouring height, the variation of the wind field distribution when the wind passed through the dam is discussed,and the optimal windproof rate is finally determined. The results of the study show that after the 20m high windproof net is placed on the downstream cofferdam of the dam area, the airflow into the foundation pit is reduced,the airflow is significantly uplifted, and the height of the low-speed wind area above the dam top is significantly increased, forming a safe area which is beneficial to construction. In addition, due to the wind resistance, the backflow at the bottom of the foundation pit is existing, the flow in the foundation pit is not stable,and the flow field is chaotic when the dam is low, which can result in a more complicated wind field structure when the top of the dam is below 620m. Before the dam is raised to 680m, the windproof net scheme can form more effective protection for each working face, and the optimal windproof rate of the windproof net is 0.5-0.67.
作者
黄章飞
安婳娟
HUANG Zhang-fei;AN Hua-juan(Pan Tianshou College of Architecture,Art and Design,Ningbo University)
出处
《智能建筑与智慧城市》
2022年第8期15-22,共8页
Intelligent Building & Smart City
基金
浙江省自然科学基金青年基金项目,项目编号:LQ17E080006。
关键词
山区风场
数值模拟
风场特性
挡风率
湍流模型
mountain wind field
numerical simulation
wind field characteristics
windproof rate
turbulence mode
