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以天然挺水植物茭草、芦苇、水葱及模拟植物PVC管为试验材料并种植于大结构混凝土明渠中,研究其在流量及种植密度相同条件下明渠中水流的三维时均流速、脉动强度及雷诺切应力的分布特点。结果表明,明渠水流流速垂线更符合抛物线分布;天然挺水植物之间、天然挺水植物与PVC管间的时均流速分布相差较大,难以用一种分布模式描述;含挺水植物水流紊流特性表现出明显的各向异性;紊动强度与植物的生长形态及柔韧性密切相关;除水葱外,芦苇、茭草及PVC管的雷诺切应力-ρu′zu′x基本接近;相比天然挺水植物PVC管对水流切应力-ρu′yu′z影响最为显著;切应力-ρu′xu′y垂线分布于相对水深0.5处出现极值,总体呈ε形状。
In order to study the three-dimensional average velocity of water flow in open channels under the same flow rate and planting density, the pulsating strength of pulsatillae, reeds, water onions and simulated plant PVC pipes were planted in open channels of large concrete structures. And Reynolds stress distribution characteristics. The results show that the vertical flow velocity of open channel is more in line with the parabola distribution. The seasonal flow velocity distribution between natural emergent plants and between natural emergent plants and PVC pipes is quite different and it is difficult to describe with a distribution model. Turbulent characteristics showed obvious anisotropy; turbulence intensity was closely related to the growth morphology and flexibility of plants; Reynolds stress-pu’zu’x of reed, Compared with natural emergent plants, PVC pipe has the most obvious influence on the shear stress of flow-pu’yu’z. The shear stress-pu’xu’y vertical distribution shows the extreme value at the relative water depth of 0.5, showing an overall ε shape.