| 摘要: |
| 矩形断面中流动的水流，在边壁附近其特征表现为三维性。依据试验资料，论证了笔者提出的水力半径分割原则，在角区附近存在一条雷诺应力为零的曲线，二次流不穿越该线，两个方向相反的二次流分别存在于分割线上、下。在此基础上，从流速分布角度论证了水力半径分割曲线的存在；通过整理试验资料发现，同一根垂线上，当高度越过分割线时，其流速分布曲线偏离对数规律，需用另一区域的对数规律描述。并提出了断面流速的计算方法。 |
| 关键词: 三维水流，流速分布，水力半径分割法，紊动结构 |
| DOI： |
| 分类号:TV131.3 |
| 基金项目: |
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| On turbulent structure of three - dimensional flow |
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Yang Shuqing
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Yang Shuqing (Nanjing Hydraulic Research Institute )Zhu Xuan (Nanjing Higher College of communications )
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| Abstract: |
| This paper deals mainly with laws of velocity distribution and the characters of secondary vector, Reynolds stress and intensity of velocity fluctuation in three dimensional flow to verify authors' theory. According id the partition method of hydraulic radius,the velocity profile normal of the boundary can be described by Prandtl - Karman formula if the friction velocities in formula are replaced with the location and overall friction velocities respectively determined by author's method.Tracy's experimental data in a smooth rectangular duct is in good agreement with the formulas presented in this paper. This paper also describes the area and shape of secondary vetor and explains the reason of deflection of maximum velocity near axis in conner region and presents formulas to describe the intensity of velocity fluctuation. |
| Key words: three - dimentional flow,velocity distribution,partition method of hydraulic radius,turbulent structure |
