Wind Field Simulation Of Direct Current Suction Type Wind Tunnel In Hunan University Of Science And Technology

The simulation of boundary layer is the first precondition of wind tunnel test. To ensure the accuracy of wind tunnel test results, it is important to simulate the atmospheric boundary layer in the test section, and do the preparatory work for the wind tunnel tests. This paper used passive device of spires, roughness element, baffles to simulate atmospheric boundary layer wind field, and obtained an average wind velocity profile and intensity profile that meet the Chinese standard specification.The contents of paper lists as follows:(1)The basic situation of the wind tunnel laboratory in the domestic and foreign were introduced; The theory of atmospheric boundary layer and the two methods of simulation the atmospheric boundary layer wind field including the active and passive simulation methods also introduced, passive simulation method will be used in this paper.(2)The wind tunnel laboratory of the Hunan University of Science and Technology,test equipment and the passive devices of spires and roughness elements, baffles were introduced.(3)The paper used the passive devices of spires and roughness elements, baffles to simulation 1:25 to 1:300 ratio of different landforms in wind field,and all test data were summarized for continuing to use easily. The passive devices of spires and roughness elements, baffles of quantitative changed to study the effects of passive devices on the wind field.The results showed that: the number of wedge and bottom width had no effect on the mean wind speed profile, but the turbulence intensity increased.The number of rows of roughness elements affect the turbulence profile, the changing of the roughness size and roughness element encryption, staggered arrangement could increase the turbulence intensity,and the turbulence effect was more obvious effects when the layout was close to the turntable.Baffle had significant influence on wind field,trapezoidal baffle arranged in the bottom of the spires could increase the turbulence intensity and decreased the mean wind speed; The saw-tooth baffle can be increased throughout the turbulence intensity profile; The scope of rectangular baffle with wedge on the location of the spire on its location in the relevant,change the position of the rectangular baffle specified height increased turbulence intensity,but it was based on the actual situation of the wind field, increasing the width and number of rectangular baffles, or easy to make the mean wind speed profile and turbulence intensity profile of the cross-sectional sectional mutates.(4)Pressure test on low-rise buildings was carried out,the results obtained from the wind tunnel test data compared with results of Tokyo University of Technology,and verified the effectiveness of the wind field.