Mixing Characteristics of Inclined Turbulent Dense Jets

  • Ilias G. PapakonstantisEmail author
  • Evangelia I. Tsatsara
Original Article


Experiments were conducted in a tank containing motionless water for studying mixing characteristics of inclined turbulent dense jets. The densimetric Froude number varied between 18 and 49. The experiments included concentration measurements conducted by means of a micro-scale conductivity probe for three discharge angles, namely 35o, 50o and 70o to the horizontal. The vertical distributions of the dimensionless time-averaged concentration and the dimensionless RMS concentration (concentration turbulent intensity) at the location of the terminal height of rise were found to be asymmetric. The (maximum) centerline height at the horizontal location of the terminal height and the horizontal distance from the source to the jet centerline at the region where the flow returns to the source level were estimated. The minimum dilutions at the maximum centerline height and the return flow region were also determined. All results were normalized according to dimensional analysis. Detailed comparisons between the present and previous results were conducted, presenting a good agreement. The variation of the mixing characteristics with discharge angle was investigated. Correlations between the dimensionless geometric characteristics of the jet centerline and the discharge angle were obtained for discharge angles between 35o and 75o.


Desalination brines Negatively buoyant jets Inclined turbulent jets Concentration distributions Dilution 



The technical assistance provided by Mr. I. Patselis, technician of the Laboratory of Applied Hydraulics of NTUA, is acknowledged.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Ilias G. Papakonstantis
    • 1
    Email author
  • Evangelia I. Tsatsara
    • 1
    • 2
  1. 1.Laboratory of Applied Hydraulics, Department of Water Resources and Environmental Engineering, School of Civil EngineeringNational Technical University of AthensZografouGreece
  2. 2.Agios StefanosGreece

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