由于水流中植物的存在,使推移质泥沙运动规律变得更为复杂,目前,含植物水流中推移质泥沙运动的研究成果较少. 实验研究了含淹没柔性植物水流中,不同植物密度及水深对时均流速、脉动强度、泥沙起动流速以及推移质输沙率的影响. 结果表明,在植物顶部以下,有植物时的时均流速明显小于无植物时的流速,而脉动强度大于无植物时的脉动强度;当水深相同时,随着植物密度的增大,泥沙起动流速呈逐渐减小的趋势,并与植物密度呈较好的三次方多项式相关关系;植物密度对推移质输沙率的影响并非呈单一变化规律,随着植物密度的增大,推移质输沙率呈先增大然后逐渐减小的趋势,当植物密度相同时,水深越小,泥沙起动流速越小,推移质输沙率越大.%Due to the existence of vegetation in water, the bed load sediment motion law becomes very complex. At present, the studies on bed load sediment movement in vegetated flows is relative rare. The effects of submerged flexible vegetation on flow velocities, turbulence intensities, initial velocity and bed load discharge rate are studied experimentally. The main experimental results showed that under the top of the vegetation, the time-average velocity of vegetated flow is obviously smaller than that of the non-vegetated flow, while the turbulence intensity is stronger than that of the non -vegetated flow. For the same water depth, with the increase of the vegetation density, the initial velocity of the sediment decreases gradually and shows a good cubic relation with the vegetation density. The effect of vegetation density on the bed load discharge rate is diverse. With the increase of the vegetation density, the bed load discharge rate increases at first and then decreases. For the same vegetation density, with the decrease of the water depth, the incipient velocity of the sediment decreases and the bed load discharge rate increases.
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