Journal of Water Resource and Hydraulic Engineering (JWRHE)
An Open Access Journal
ISSN:2306-7705(Print)      ISSN:2306-7691(Online)
Editor-in-Chief:
Prof. Bill Hu, Florida State University, USA
Frequency: Quarterly
Free-surface Profiles and Turbulence Characteristics in Skimming Flows along Stepped Chutes
Full Paper(PDF, 6844KB)
Abstract:
The behavior of the free surface in skimming flows along stepped chutes is investigated for the step ratio 1V:1H. Data were collected using high frequency ultrasound probes. The measurements included mean surface profiles, statistical parameters related to the surface position, aeration inception point, water depth at the inception point and transition length. The measurements were related to turbulence parameters at the free surface. The measurement methodology was adequate for both the black-water and the white-water regions. Characteristic relations are developed for different variables defined for skimming flows. The results demonstrate regions of increasing and decreasing turbulence in the transition between the black-water and the white-water flows, and a region of decay of turbulence, related to the distance needed to attain the quasi-uniform flow of the white-water.
Keywords:Air-Water Free Surfaces; Stepped Chutes; Turbulence; Skimming Flows; Multiphase Flows
Author: André Luiz Andrade Simões1, Harry Edmar Schulz2, Rodrigo Melo Porto3, John Stephen Gulliver4
1.Dept. Civil Engg., University Salvador, Av. Juracy Magalh?es Junior, 105, CEP 41940-060, Salvador, BA, Brazil
2.Nucleus of Thermal Sciences & Engg., University of S?o Paulo, Av. do Trabalhador S?o-carlense, 400, CEP 13566-590,S?o Carlos, S.P., Brazil
3.Dept. Hydraulics & Sanitary Engg., University of S?o Paulo, Av. do Trabalhador S?o-carlense, 400, CEP 13566-590,S?o Carlos, S.P., Brazil
4.Saint Anthony Falls Lab., Dept. Civil Engg., University of Minnesota, 2 Third Avenue SE, MN 55414, USA
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