摘要: |
梅花形阵列粗糙是常见的床面粗糙形态。采用不同颗粒大小和排列间距的圆形玻璃珠制作了3种梅花形阵列粗糙床面,基于明渠紊流的PIV水槽试验资料,探讨了无量纲纵向紊动强度Tu、雷诺应力R和紊动能E的分布规律,结果表明:① 颗粒顶部以上区域的Tu、R、E沿程基本呈条带状变化,受颗粒影响较小,而颗粒顶部以下区域的Tu、R、E受颗粒影响明显,沿程变化相对复杂,表现出一定周期性和分区性,并可分为颗粒区和粒间区。② 颗粒顶部以上区域Tu、R、E的垂线分布基本重合,颗粒顶部以下区域Tu、R、E在颗粒区的垂线分布波动明显,分布曲线呈“S”和倒“L”等形状。③ 粒间区各象限的R、E沿程变化较为平缓,接近水平线,第2、4象限的R、E总体大于第1、3象限;颗粒区各象限的R、E沿程分布呈“∪”状并在沿程位置参数x+ = 0附近有最小值。研究成果对鱼道及航道工程设计等具有一定的指导意义。 |
关键词: 梅花形阵列粗糙 明渠水流 紊动强度 雷诺应力 紊动能 |
DOI: |
分类号:TV143.5 |
基金项目: |
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Turbulence characteristics in open channel with glass-sphere quincunx arrays |
ZHONG Liang1, GE Chenxi2, SUN Jianyun3
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1.National Engineering Research Center for Inland Waterway Regulation,Chongqing Jiaotong University;2.Key Laboratory of Hydraulic and Waterway Engineering of the Ministry of Education,Chongqing Jiaotong University;3.Chongqing Tongwang water conservancy and Hydropower Engineering Design Co,Ltd
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Abstract: |
Quincunx array roughness is a common bed surface roughness. Three kinds of quincunx array rough bed surfaces were made by round glass beads with different particle sizes and arrangement intervals. Based on the experimental data of PIV flume for open channel turbulence, the distribution of dimensionless longitudinal turbulence intensity Tu, Reynolds stress R and turbulent kinetic energy E were discussed, and the results shows that Tu, R, E in the area above the top of the particles show a strip-shaped change, which is less affected by the particles, while Tu, R, E in the area below the top of the particles are obviously affected by the particles, and the longitudinal variation is relatively complex, which showing a certain periodicity and regionality, and can be divided into sphere region(SR)and inter-sphere region(ISR). The vertical distribution of Tu, R and E above the top of the particle basically coincides with each other, while the vertical distribution of Tu, R and E below the top of the particle fluctuates obviously, and the distribution curve is in the shape of "S" and inverted "L". The longitudinal variations of R and E of different quadrants in the ISR are smoothly and close to the horizontal line, the values of R and E in the 2nd,4th quadrant are generally greater than that of the 1st, 3rd quadrant. However, in the SR, the distribution of R and E showed a ∪-like shape and there are minimum values near the position of x+ = 0. The research results have certain guiding significance for the design of fishway and waterway engineering. |
Key words: rough bed with quincunx arrays open channel flow turbulence intensity Reynolds stress turbulent kinetic energy |