| 摘要: |
| 采用RNGk-ε紊流模型,结合万家寨引黄入晋工程第1区段压力管道出口多喷孔淹没射流消能,进行了三维数值模拟研究,对不同喷孔个数时流场的时均特性和紊动特性进行了比较,分析讨论了多孔淹没射流进入消力池后的水流运动规律与消能机理。结果表明,射流动量的分散程度是决定消能效果的关键,在保持孔口总面积不变的条件下,随着喷孔数的增加,消能效果显著提高,但当喷孔数增加到60个时,其变化显著减缓。多喷孔射流进入消能水体后,射流水股与周围水体接触面积极大增加,在距离喷孔出口0.41 m左右时射流能量迅速衰减,加之各水股间的相互卷吸、掺混,形成了多个强剪切消能区,消能率较高。同时,由于各漩滚的相互作用,可有效地减小其对消力池固壁的冲刷。 |
| 关键词: 多孔淹没射流 三维流场 紊流数值模拟 消能机理 |
| DOI： |
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| 基金项目:山西省科学技术厅科技攻关项目（041086） |
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| Numerical simulation and analysis on energy dissipation of 3-D flow field of multiple submerged jets into plunge pool |
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| Abstract: |
| The RNGk-ε model is applied to simulate the 3-D flow field on energy dissipation of multiple jets for pipe outlet of Wanjiazhai Yellow River Diversion Project (YRDP) in this paper.A contraste study of the time averaged and turbulent features of flow field among different numbers of nozzles has been summarized,and the flow structure and mechanism of energy dissipation of this kind have been also revealed by this numerical model.It is found that the effect of energy dissipation is strongly related to the dispersivity of the jet momentum and it remarkably improves with the increase of the number of nozzles,but the variation slows down obviously as the number of nozzle increases to 60.The results show that the entrainment and mixing of the multiple jets increase among multiple jets,with the range of 0.41 m far from the nozzles the jet energy declines rapidly,forms several strong shear flows,and enhances the effect of energy dissipation.At the same time,the effect of erosion on plunge pool wall is reduced due to the interaction among eddies. |
| Key words: multiple submerged jets,3-D flow field,numerical simulation of turbulent flow,mechanism of energy dissipation |
