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针对云南滇池高原湖泊湿地植物生长种类,采用水槽实验,进行了三种流量、三种不同生长期植物的植物带前、中、后断面沿程流速和垂线流速分布的实验,通过水槽实验研究,分析了植物生长对水流结构影响机理。实验研究表明:①种植物时,植物带前各断面流速比无植物时都有一定的减小,植物对水流有明显的阻滞作用。植物带段过流流速沿程逐渐增加,在一定距离后达到最大值;同一流量条件下,随植物的生长,对水流的阻滞作用越明显,流速变化越大。植物大小一定时,流量越大,植物中流速达到最大值的距离越长。②植物段水流垂线流速分布与明渠恒定流垂线流速分布规律有所不同,植物底部流速比明渠恒定流要小,水面流速比明渠恒定流要大;植物带后水流流态恢复到明渠恒定流流态需要一定的距离。
Aiming at the types of plant growth in lake and wetland of Dianchi Plateau in Yunnan Province, experiment on the distribution of flow velocity and vertical velocity along the front, middle and back sections of the plants with three flow rates and three different growth stages was carried out by using the sink experiment. The mechanism of plant growth on water flow structure was analyzed. Experimental studies show that: (1) When plants are grown, the flow velocity in each section before the belt decreases to a certain extent compared with that in the absence of plants, and the plants have obvious retardation effects on the water flow. The flow velocity of the over-flow in the plant section gradually increases along the process and reaches the maximum after a certain distance. Under the same flow conditions, with the growth of the plant, the blocking effect on the flow of water is more obvious and the change of the flow rate is greater. When the plant size is constant, the greater the flow rate, the longer the flow rate in the plant reaches the maximum value. ② The vertical distribution of vertical flow velocity in vegetative section is different from that of constant flow in open channel. The flow velocity at plant bottom is smaller than that in open channel, and the surface flow rate is larger than that in open channel. Stream flow requires a certain distance.