Experimental study on pressure and aeration characteristics in stepped chute flows

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• 作者：WeiLin Xu (1)
  ShuJing Luo (1)
  QiuWen Zheng (1)
  Jing Luo (1)
  
  1. State Key Laboratory of Hydraulics and Mountain River Engineering ; Sichuan University ; Chengdu ; 610065 ; China
  
• 关键词：stepped spillway ; time ; averaged pressure ; aerated flow ; cavitation erosion
• 刊名：SCIENCE CHINA Technological Sciences
• 出版年：2015
• 出版时间：April 2015
• 年：2015
• 卷：58
• 期：4
• 页码：720-726
• 全文大小：978 KB
• 参考文献：1. Zhang, Z C H, Zeng, D Y, Liu, Y F (2003) Experimental investigation on the characteristic of air entrainment on the stepped spillways (in Chinese). Chin J Appl Mech 20: pp. 97-100
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  5. Sanchez, M (2000) Pressure field in skimming flow over a stepped spillways. Proceeding Intl. Workshop on Hydraulics of Stepped Spillways, VAW, ETH-Zurich, H.E. Minor and W.H. Hager. Balkema. pp. 137-145
  6. Matos, J, Quintela, A (2000) Air entrainment and safety against cavitation damage in stepped spillways over RCC dams. Proceeding Intl. Workshop on Hydraulics of Stepped Spillways, VAW, ETH-Zurich, H.E. Minor and W.H. Hager. Balkema. pp. 69-76
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• 刊物类别：Engineering
• 刊物主题：Chinese Library of Science
  Engineering, general
  
• 出版者：Science China Press, co-published with Springer
• ISSN：1869-1900

文摘

The free flow on the step surfaces has received much attention for its representative body type, flow structure, water-air two phase flow, cavitation, and many complex issues. The experiments about the time-averaged pressure and aeration concentration distribution on the step surface show that the vertical plane of steps will inevitably experience negative pressure, which must rely on adequate aeration concentration to avoid cavitation damage. However, the self-aerated flow at the head section has a relatively low aeration concentration, and the concentration of the entire steps decreases with the increasing of weir head, the minimum appears in the vicinity of the corner, and the location is close to the minimum pressure. Thus, it is necessary to set aerator in the upstream end of the step surfaces to avoid cavitation damage.