Research On Wind Field Characteristics Of Mountain Canyon

In recent years,more and more high flexible and long-span spatial structures have been developed and constructed in mountainous and hilly areas,and these structures are typical wind sensitive structures.At present,the normative provisions on mountain terrain wind field in various countries are relatively simple.Only for the two-dimensional mountain terrain,it is proposed to use the wind speed increase coefficient to consider the mountain wind field,and there are no provisions on the law of wind field under the three-dimensional mountain terrain and the canyon effect formed by the two mountains.However,in the field of wind engineering research,the wind field of mountainous terrain is obviously different from that of flat terrain.The complex terrain and landform of mountainous area will significantly change the wind field characteristics such as the wind speed and turbulence structure of near surface layer flowing wind,so as to form the unique wind field structure characteristics of mountainous terrain.This paper mainly analyzes the wind field distribution characteristics at the top,interior and hillside of the canyon under the influence of various factors through numerical simulation method and combined with the existing wind tunnel test data,and puts forward the variation law of wind profile of mountain canyon.The relevant conclusions can provide reference for building site selection in mountain area and building wind resistance design under Canyon terrain.The main research contents are as follows:(1)The numerical simulation method is used to study the numerical simulation of the mountain canyon model under a typical working condition.By comparing the numerical simulation results of the mountain canyon model under different grid division forms,turbulence models and various parameter settings with the wind tunnel test data under the corresponding working condition,the parameter settings in the numerical simulation of the mountain canyon are determined,Verify the accuracy of numerical simulation.(2)Considering the influence of various factors(mountain spacing,slope,length and height)on the average wind speed profile of the near ground wind field around the mountain,the mountain canyon model under different conditions is numerically simulated,and combined with the existing wind tunnel test data under the corresponding influencing factors,the influence of different factors on the average wind speed profile inside the canyon under different wind directions is analyzed,Study the variation law of wind speed profile.(3)Combined with the existing wind tunnel test data and numerical simulation results,the influence of various factors of Canyon mountain(mountain spacing,slope,length and height)on the average wind speed profile inside the canyon is analyzed.On this basis,the formula of mountain canyon wind profile is proposed to determine the shape of mountain Canyon wind field.The research results can provide a reference for the wind resistance design of buildings under Canyon terrain.