Study On Wind Tunnel Simulation Of Turbulent Wind Based On Rotating Wing Grid

With the development of bridge engineering,the modern bridge gradually developed in the direction of bigger span,and the wind resistance performance of bridge structure gradually increased.Wind tunnel test is one of the main methods to study the wind stability of bridge structure,and it is necessary to further ensure the accuracy of wind tunnel test.However,at present,wind tunnel test at home and abroad is usually carried out by passive simulation method such as wedge-roughness method to simulate the atmospheric boundary layer wind field,there is a drawback that the integral scale is too small and attenuated with height,and cannot meet the wind tunnel test requirements of the large scale model.In order to solve this problem,this paper has developed a rotary gland device to carry out wind tunnel test to study the active simulation of simulated flow field related characteristics,including the following work:1.The development of the rotary wing device,the design of the corresponding wind tunnel test and relying on the Southwest Jiaotong University XNJD-1 wind tunnel laboratory for flow field test.2.Through the measurement of the spectral characteristics of the flow field,the turbulence intensity,the turbulence integral scale and the spatial correlation,it is found that the flow field simulated by the rotating wing device is uniform,the sinusoidal characteristic flow field of single frequency,the pulsating energy Which is consistent with the rotational frequency of the wing gates.At the same time,the turbulence intensity of the flow field is relatively stable in the range of 4.5m?7.5m from the rotating girders.The turbulence integral scale decreases with the increase of the rotational frequency of the gates,and the maximum integral scale Reaching 29m;spatial correlation is better,the correlation coefficient is about 0.9.3.The results of 4.7m/s?6.8m/s?8.7m/s show that the turbulence intensity in the low frequency region decreases with the increase of the wind speed,and the turbulence intensity in the high frequency region decreases with the wind speed The change of the rotational frequency has a great influence on the vertical wind component of the turbulence intensity at the same wind speed.The grating device developed in this paper preliminary solves the problem that the turbulence integral of the turbulence field is too small to simulate the turbulence of the turbulence field.At the same time,the pulsating wind with the sinusoidal wind is simulated to meet the special flow field requirement of the pneumatic admittance...