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Flow Chocking Characteristics of Leak-Floor Flip Buckets

  • Shu-fang Li
  • Ji-wei Yang
Conference paper
Part of the Environmental Earth Sciences book series (EESCI)

Abstract

Leak-floor flip bucket is a new type of flip bucket recently proposed. It has the advantages of decreasing flow choking on the bucket in small flow regimes and improving energy dissipation by a typical long-narrow nappe. However, if the structure parameters are designed unreasonably, flow choking may also occur on the bucket if the impact location of the lower jet trajectory is too near to the base of the structure, and will threaten the safety of the dam. The purpose of this paper is to study the critical conditions when flow choking begins to disappear or appear on the leak-floor flip bucket, during the increasing and decreasing discharge regimes, respectively. Five leak-floor flip bucket models were conducted, and one circular-shaped flip bucket was prepared for comparison. The critical conditions were investigated under a systematic variation of the approach flow depth, gap width and gap length. It concludes that the critical Froude numbers are primarily influenced by the relative bucket height and the area ratio of the gap; empirical equations for the prediction of critical conditions are obtained and conformed to the test data reasonably.

Keywords

Leak-floor flip bucket Flow choking Critical condition Dissipater 

Notes

Acknowledgements

This research was financially supported by the National Science Foundation. Thanks to the guidance of Professor Jianhua Wu and Fei Ma in Hohai University. Thanks to the proposal of Professor Jiwei Yang in Hebei University of Engineering.

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.College of Water Conservancy and Hydropower EngineeringHebei University of EngineeringHandanChina
  2. 2.College of Water Conservancy and Hydropower EngineeringHohai UniversityNanjingChina

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