Wind Tunnel Simulation Experiment Study On The Mechanism Of Wind-proof And Sand-fixing With Wing Bag Sand Barrier

The wing bag sand barrier is a combined sand barrier designed according to the bottom bag fixed quicksand and the wings on the bag fluctuate in the wind to weaken the wind speed.It has been granted a patent.The experiment was carried out in the wind tunnel of the Key Laboratory of Desert and Desertification of the Chinese Academy of Sciences,Zhongwei,Ningxia,with3 different bottom bag diameters（10cm,12cm,15cm）and 9 specifications（corresponding to the height of the wings 10cm,15cm,20cm）wing bag sand barriers.The wind velocity flow field,the structure of sand flow,the characteristics of sand transport and the situation of wind erosion wind accumulation are studied,and the results show that:（1）The wind speed between and behind the barrier of different specifications of wing bag sand barriers is significantly reduced and there are differences.When the wind speed is 5m·s^-1,the wind-proof efficiency of the 9types of wing bag sand barriers is between 50.7%-82.5%;when the wind speed is 8m·s^-1,the wind-proof efficiency is 56.25%-76.75%;the wind speed is12m·s^-1At the same time,the windproof efficiency is 63.04%-78.17%.（2）The wing bag sand barrier can reduce the front,middle,and rear wind speeds.The larger the bottom bag diameter of the same wing height,the lower the wind speed at the front and middle position of the sand barrier;the same wing height sand barrier with different bottom bag diameters will cause weaker wind speeds afterwards The zone distance range is the same,and the greater the height of the wings,the farther the distance in the weak wind speed zone.（3）The wing bag sand barriers of different specifications change the trajectory of the sand flow on the surface and effectively intercept the sand particles in the sand flow on the surface.Compared with the bag-shaped sand barrier,the wing bag sand barrier reduces the sand transport by an average of85.2%.When the wind speed is 5m·s^-1,the wing bag sand barriers of different specifications can reduce the sand transport by 70.1%-98%compared with the no sand barrier;when the wind speed is 8m·s^-1the sand transport will be reduced by 14.2%-95%;when the wind speed is 12m·s^-1,the sediment transport will be reduced by 18%-80.1%.（4）Wing bag sand barriers of different specifications were piled up before and after the wind erosion barrier,and wind erosion occurred to different degrees.When the wind speed is 8m·s^-1and 12m·s^-1,the wind erosion of the sand barrier with different bottom bag diameters and wings height of 20cm is the largest.Two types of sand barriers with a bottom bag diameter of 10cm reduce wind erosion by 64%-66%;sand barriers with a bottom bag diameter of 12cm reduce wind erosion by 27.1%-34.4%.The 15cm diameter of the bottom bag reduces the amount of wind erosion by44.82%-66.58%.（5）The wing bag sand barrier for wind-proof and sand-fixing configuration mode is when the wind speed is 5m·s^-1,the bottom bag diameter is 15cm,and the wing height 15cm is the best;when the wind speed is 8m·s^-1,the bottom bag diameter is 12cm and the wings height is 15cm.The bag sand barrier has the best wind-proof and sand-fixing effect;when the wind speed is12m·s^-1,the effect of the wing bag sand barrier with the bottom bag diameter of 15cm and the wings height of 15cm is the most significant.