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CLC number: TV131

On-line Access: 2013-04-30

Received: 2012-09-21

Revision Accepted: 2013-01-21

Crosschecked: 2013-04-19

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Journal of Zhejiang University SCIENCE A 2013 Vol.14 No.5 P.362-370

http://doi.org/10.1631/jzus.A1200312


Influence of aeration and initial water thickness on axial velocity attenuation of jet flows*


Author(s):  Wang-ru Wei1, Jun Deng1, Bin Liu2

Affiliation(s):  1. State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China; more

Corresponding email(s):   wangru_wei@hotmail.com

Key Words:  Velocity, Aeration, Initial water thickness, Jet flows


Wang-ru Wei, Jun Deng, Bin Liu. Influence of aeration and initial water thickness on axial velocity attenuation of jet flows[J]. Journal of Zhejiang University Science A, 2013, 14(5): 362-370.

@article{title="Influence of aeration and initial water thickness on axial velocity attenuation of jet flows",
author="Wang-ru Wei, Jun Deng, Bin Liu",
journal="Journal of Zhejiang University Science A",
volume="14",
number="5",
pages="362-370",
year="2013",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.A1200312"
}

%0 Journal Article
%T Influence of aeration and initial water thickness on axial velocity attenuation of jet flows
%A Wang-ru Wei
%A Jun Deng
%A Bin Liu
%J Journal of Zhejiang University SCIENCE A
%V 14
%N 5
%P 362-370
%@ 1673-565X
%D 2013
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.A1200312

TY - JOUR
T1 - Influence of aeration and initial water thickness on axial velocity attenuation of jet flows
A1 - Wang-ru Wei
A1 - Jun Deng
A1 - Bin Liu
J0 - Journal of Zhejiang University Science A
VL - 14
IS - 5
SP - 362
EP - 370
%@ 1673-565X
Y1 - 2013
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.A1200312


Abstract: 
With the development of ski-jump energy dissipation for high and large discharge among the hydraulic projects, the effects of characteristics of water flow on energy dissipation are increasingly important. In the present study, the effects of aeration and the initial water thickness on axial velocity attenuation of jet flow were analyzed, using variance analysis and numerical calculated methods. From the analysis of test data, both of the air concentration and initial water thickness are sensitive factors for the axial velocity attenuation of jet flow along the axial way, and there is no significant interaction effect between the aeration and initial water thickness. aeration has a more significant effect on the axial velocity attenuation of jet flow. Decreasing the initial water thickness of jet flow can reduce the length of jet core, and make the initial position of axial velocity attenuation closer to the nozzle exit. The numerical calculation results show that aeration can contribute to the enhancement of entrainment ability of jet flow, which may improve the interaction between jet flow and surroundings. For ski-jump energy dissipation among the hydraulic projects, combining aeration with decreasing initial water thickness of jet flow is an effective way to enhance the rate of axial velocity attenuation.

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

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