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通过风洞模拟实验研究了直立植物防沙措施的粗糙特征及其影响因素。实验结果表明 ,在各种一定风速条件下 ,对数风速廓线中的粗糙度 Z0 值随植物密度的增加呈幂函数增加 ,幂函数的指数 <1;而在各种一定植物密度条件下 ,Z0 随风速的增大而减小 ,遵循单分子增长曲线型的指数函数。根据实验结果建立的包含风速和植物密度两个因子的 Z0 的双因子综合模型对 Z0 的预测值与实验值吻合得比较好。对数风速廓线中的 Z0 是一个反映近地表气流与下垫面相互作用力学特征的物理量 ,纠正了一般认为 Z0 仅取决于下垫面性质的概念 ,在分析中 ,应区分空气动力粗糙度和下垫面粗糙度两个不同的概念。
Through the wind tunnel simulation experiment, the rough characteristics and the influencing factors of erect plant sand control were studied. The experimental results show that under certain wind speed conditions, the logarithm of the logarithmic wind speed profile Z0 increases exponentially with the increase of plant density, the exponential of power function <1; under certain plant density conditions, Z0 decreases with increasing wind speed and follows the exponential function of the monomolecular growth curve. Based on the experimental results, the two-factor Z0 integrated model including wind speed and plant density is in good agreement with the predicted value of Z0. Z0 logarithmic wind speed profile is a physical quantity that reflects the mechanical characteristics of the interaction between the near-surface air flow and the underlying surface, and corrects the notion that Z0 is only determined by the nature of the underlying surface. In the analysis, aerodynamic roughness And under the surface roughness of two different concepts.