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天然河道中植物高低不等,为了研究在淹没条件下含刚性双层植物河道的水流流速垂向分布规律,试验在矩形平底水槽中,采用PVC圆柱棒对刚性植物进行模拟,用三维多普勒超声测速仪(ADV)对流速进行测量,分析在两种不同高度植物存在的情况下流速的变化规律。试验结果表明:(1)高棒之后区域的流速分布曲线存在4个拐点,分布曲线分为5个部分,各部分水流特性各不相同。(2)短棒之后的区域的流速分布曲线存在3个拐点,分布曲线分为4个部分。这两个区域的流速分布曲线的形状在短棒之上、高棒之下的部分有所不同,其他部分大体相似。(3)短棒之下的水流速度大小不尽相同,但在高棒之上的水流流速分布逐渐收敛于一条对数曲线上,高棒之上的水流流速分布符合无植物水流水面附近的流速分布情况。
In order to study the vertical distribution of water flow velocity in a rigid bi-level plant channel under inundation conditions, rigid plants were simulated with PVC cylindrical rods in a rectangular flat-bottomed water tank. Three-dimensional Doppler The velocity of flow was measured by ultrasonic anemometer (ADV), and the variation of flow velocity in the presence of two different height plants was analyzed. The test results show that: (1) There are 4 inflection points in the flow velocity distribution curve in the area after the high rod, the distribution curve is divided into 5 parts, and the water flow characteristics of each part are different. (2) There are 3 inflection points in the flow velocity distribution curve in the area after the short rod, and the distribution curve is divided into 4 parts. The shape of the velocity profile of the two regions is above the short rod, the part under the high rod is different, and the other parts are generally similar. (3) The velocity of water flow under the short rod is not the same, but the flow velocity distribution above the high rod gradually converges on a logarithmic curve. The flow velocity distribution above the high rod matches the flow velocity near the surface without the plant water Distribution.