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风沙灾害集中地体现在风沙流对工程设施的破坏、土壤风蚀沙化的急剧恶化方面.致害原因,是飞扬沙粒在风力作用下获得大量能量.而判别风沙危害强度的大小,取决于风沙流集聚能量的高低.限于沙粒微小,相对运动速度极大,对其运动群体进行测量甚为困难,以至迄今未见风沙流能量的研究成果.风沙流是一种贴近地表的气固两相流.据研究,气流中搬运的沙量绝大部分集中在离地表10cm,尤其是贴地面5cm以下气流层中.为此,本文利用高速频闪摄影技术和环境沙风洞相结合的手段,对低层风沙流(6cm以下)的能量分布状况进行初步探讨.
The sandstorm disasters are concentrated in the destruction of engineering facilities and the sharp deterioration of soil erosion and desertification due to the sandstorm flow.The reason of the damage is that the flying sand gets a lot of energy under the action of the wind.And the magnitude of the risk of sandstorm is determined by the sand flow Concentration of energy level is limited to the small sand, the relative speed of movement is extremely large, the measurement of its movement is very difficult to the crowd, so far no research results of wind-blown flow energy.The sand flow is a close to the surface of the gas-solid two-phase flow According to the study, most of the sand transported in the air stream concentrated in the air layer 10cm above the ground, especially below the ground 5cm.Therefore, this paper makes use of the combination of high speed flash photography technology and environmental sand tunnel, Low-level sand flow (6cm below) the energy distribution of the preliminary study.