| 摘要: |
| 吸气漩涡是水利工程中进水口前常见的水力学问题，模型试验是研究进水口前漩涡特性的常用方法。目前关于漩涡特性的研究主要集中在淹没水深较大、进水口结构不变的泄洪洞以及电站进水口等，而对于弧形闸门局部开启时闸前漩涡特性的研究较少。为了研究弧形闸门前漩涡的水力特性以及黏性力和表面张力对弧形闸门前漩涡的影响，以某泄洪闸弧形闸门为研究对象，采用2个不同比尺的模型试验及理论分析方法，对弧形闸门局部开启时闸前吸气漩涡的水力特性进行了研究。结果表明，闸前漩涡是行进水流横向和纵向突然收缩共同作用的结果。弧形闸门前水面紊动较大，所以闸前漩涡频率较高，持续时间较短，闸门开度越大，闸前吸气漩涡越强。若按照弗劳德数准则设计模型试验，当来流雷诺数和韦伯数大于某一临界值时，可以忽略黏性力和表面张力影响。 |
| 关键词: 弧形闸门 漩涡 模型试验 比尺影响 雷诺数 韦伯数 |
| DOI： |
| 分类号:TV131.6 |
| 基金项目:国家自然科学基金资助项目(51479022, 2014001） |
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| Experimental studies on characteristics of vortex formed in front of radial gate |
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SUN Hongliang, LIU Yakun, ZHANG Hongyu, LIU Jiejie
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Dalian University of Technology, Dalian
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| Abstract: |
| The air core vortex is a common hydraulic problem in front of the intakes placed on the hydraulic works. A model experiment method is a usual way to study the hydraulic characteristics of the vortex in front of the intakes. At present, the previous studies of the vortex hydraulic characteristics are mainly focused on the intakes of the spillway tunnels or water intakes of the hydropower stations, which have the unchanged structures and deep water submergence. In contrast to these model tests, there is a few studies of the hydraulic characteristics of the vortex in front of the partially opened radial gate. In order to study the hydraulic characteristics of the vortex in front of the partially opened radial gate and influences of viscous force and surface tension on this vortex, the air core vortex formed in front of the partially opened radial gate of a flood releasing sluice was taken as a research object in this study. A theoretical analysis method and two comparative experiments of different scale models were carried out to study the air core vortex in front of the partially opened radial gate. The results show that the vortex formed in front of the partially opened radial gate is a result of transverse and vertical contraction of the progressive flow. And the turbulent fluctuation of the progressive flow in front of the radial gate is strong, so the vortex frequency in front of the gate is high and the inspiration duration of the vortex is short. Further, the more the radial gate opened, the stronger the intensity of the air core vortex is. If the experimental models are operated according to the Froude number similarity criterion, the influences of the viscous force and surface tension on the modeling vortex can be ignored when the Reynolds and Weber numbers are larger than a certain critical value. The research results of this paper can provide a reference and basis for future researches and engineering designs. |
| Key words: radial gate vortex model experiment scale effects Reynolds number Weber number |
