峡谷平均风空间分布特性研究

发布时间：2018-05-08 13:37

本文选题：峡谷风 + CFD　；参考：《西南交通大学》2015年硕士论文

【摘要】：风特性是抗风研究的基础,尤其对于西部山区来说,峡谷风场特性的研究对于工程抗风设计有着非常重要的参考价值。目前,风洞试验和数值模拟是风参数研究的主要手段。对于山区桥梁工程的抗风问题,虽然国内外都曾进行过一些探讨和研究,但是实测资料严重匮乏,相关的文献资料也较少,山区峡谷风特性的研究也较为肤浅,值得更为深入的探究。本文以山区峡谷桥址区的风场为研究目标,为了便于利用风洞试验和数值模拟研究峡谷的形式和坡度变化对其内部风场的影响,将峡谷抽象为简化的U型谷,变换峡谷底部宽度与斜坡倾斜角度以得到不同峡谷形式,通过数值模拟方法,建立立体几何模型,划分网格并添加边界条件,计算其内部平均风速的大小,分析风场的分布特征以及不同峡谷形式之间的关联,给出风速剖面的计算结果,推出峡谷内部平均风的空间分布规律。通过风洞试验,测量峡谷模型内部的平均风速的大小和方向,验证数值模拟方法的科学性和合理性。对数值计算结果和风洞试验结果进行整理和拟合,并参考相关文献和前人的经验,提出山区峡谷桥梁抗风设计基准风速的修正的经验公式。针对峡谷内部风速垂直分布的相关规律,分析验证了峡谷内部不同高度位置处桥梁抗风设计基准风速的修正的经验公式。根据相关资料对该风速经验公式进行验证,取得良好的结果。
[Abstract]:Wind characteristic is the foundation of wind resistance research, especially for western mountainous area, the study of canyon wind field characteristics has very important reference value for engineering wind-resistant design. At present, wind tunnel test and numerical simulation are the main means of wind parameter research. As for the wind-resistant problem of bridge engineering in mountainous areas, although there have been some discussions and studies both at home and abroad, the measured data are seriously scarce, the relevant literature is also less, and the study of wind characteristics of mountain canyons is also superficial. It is worth exploring more deeply. In this paper, the wind field in the mountain canyon bridge site is taken as the research object. In order to study the influence of the canyon form and slope change on the inner wind field by wind tunnel test and numerical simulation, the canyon is abstracted as a simplified U-shaped valley. Different canyon forms are obtained by changing the width of the canyon bottom and the slope inclination angle. Through the numerical simulation method, the three-dimensional geometry model is established, the grid is divided and the boundary conditions are added to calculate the magnitude of the average wind speed inside the canyon. The distribution characteristics of wind field and the correlation between different canyons are analyzed. The results of wind speed profile are given and the spatial distribution of mean wind in canyons is deduced. Through wind tunnel test, the magnitude and direction of the mean wind speed inside the canyon model were measured to verify the scientific and reasonable of the numerical simulation method. The numerical calculation results and wind tunnel test results are arranged and fitted. With reference to relevant literature and previous experience, an empirical formula for revising the wind speed of wind resistant design of mountain canyon bridges is put forward. According to the correlation law of vertical distribution of wind speed in canyons, the modified empirical formula of wind resistance design benchmark wind speed of bridges at different heights in canyons is analyzed and verified. According to the relevant data, the empirical formula of wind speed is verified and good results are obtained.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U442

【参考文献】