| China is one of the serious threat desertification country, desertification serious threat to the ecological safety. The checkerboard sand barrier is the most effective and use of the most technical measures in wind and sand control project, and plays an important role in the vegetation recovery in the green belt and management of the tall mobile sand dunes. First, according to the flow field characteristics within the protected area of the checkerboard sand barriers, a theoretical model, that is one-row-vortex model, is suggested to simulate the flow field in the straw checkerboard barriers. On this basis, we further considered the cross-section of sand barrier, gave the correspondence between distance and height of checkerboard sand barriers of the different forms of cross-section checkerboard barriers. In this paper, we calculated rectangular, triangular and trapezoidal cross-section, we found the section height increased as the cross-section width decreased, which has important practical significance in guiding the project.In this paper, the spatial variation of wind speed along straw checkerboard barriers belt were studied by computational fluid dynamics. For the spatial variation of wind speed along straw checkerboard barriers, our results show that the spatial variation of wind speed along straw checkerboard sand barriers belt can be divided into three stages, i.e., descent stage, stable stage and recovery stage, and the variation of wind speed with height satisfy three different log-linear functions, i.e., the log-linear function below the straw height, the log-linear function between the straw height and the critical height, and the log-linear function above the critical height. The straw height and the leaf area density have obvious influence on the spatial variation of wind speed. Furthermore, the prediction formula of sand transport rate above straw checkerboard was given based on the ratio of near-surface wind speed and the incoming wind speed. |
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