Experimental Investigation of Flow Field Due to Dual Offset Jets

Document Type : Research Article

Authors

1 Assistant Professor, Kharazmi University, Tehran, Iran

2 Professor, Hydraulic Engineering, Water Research Institute, Tarbiat Modares University, Tehran, Iran

3 Ex-Graduated Student, Tarbiat Modares University, Tehran, Iran

Abstract

In this research the flow field and the correlation between the flow field and scour due to double jets in the preliminary stages are investigated. Two experiments were conducted with different densimetric Froude number in fixed bed and high tailwater depth condition. Comparisons between scour process and flow field are presented. According to the results of this research, appropriate parameters are presented to find the non-dimension at profiles, non-dimensional velocity decay, and velocity development in flow depth and non-dimensional form of velocity fluctuation such as velocity fluctuation component in vertical and streamwise directions and Reynolds stresses. Good agreement was found between present data and previous researchers data. The Reynolds stress investigations show that, the shear stress variation using different methods are approximately the same and the estimation of the shear stress with vertical velocity fluctuation gives larger values. In addition, difference between the bed shear stress estimation using different methods are large in the regions with higher values. The estimation of shear stress with Reynolds stresses has better correlation with scour process. The angles of ejection and sweep events do not have good correlation with scour process. 

Keywords

References

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History

  • Receive Date: 19 February 2017
  • Revise Date: 11 May 2017
  • Accept Date: 03 June 2017

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