Evolution of a Negatively Buoyant Jet in the Near and Intermediate Field

Research output: Chapter in Book/Report/Conference proceedingPaper in conference proceeding


The most common situation connection with freshwater production from sea water (desalination) is producing a brine waste stream, usually discharged back into sea water. The purpose of this study is to explore the behavior of a dense jet and bottom plume, composed of brine water of heavier effluent into a quiescent homogeneous ambient, discharged into a receiving body of lighter fresh water (tank).In this study, a mathematical model was developed to simulate the jet and plume behavior in order to determine the optimum discharge conditions for different scenarios. The model was divided into two sub-models, describing respectively the near and intermediate field properties of the discharge for different inclinations and bottom slope. The lateral spreading and electrical conductivity was also described through a generalization of measured data.
A Matlab code developed describing the lateral spreading and centerline dilution of buoyant jet and plumes for near and intermediate field was developed. The model produces results in acceptable agreement with data and observations, even though some improvements should be made in order to give the correct weight to the bottom slope parameter and to reduce the need for user calibration. An overall assessment of the CORMIX software behavior cannot be made; in our case (i.e. small scale) the software was not giving simulation results that reproduced the data.
This study has limited result for only 16% bottom slope and 30 degrees inclination. Concentration was improved with the bottom slope by 10% than the horizontal bottoms and improved by about 40% with bottom slope together with inclination of 30 degrees. The suggestion in the practical applications concerning desalination brines and similar discharge of heavy wastes is to have inclination and bottom slope together.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Water Engineering
  • Other Social Sciences


  • Desalination, Negatively Buoyant Jet, Near and Intermediate Field, Matlab, CORMIX, Brine discharge.
Original languageEnglish
Title of host publicationInternational Desalination Association (IDA) World Congress
PublisherIDA-International Desalination Association
Number of pages12
Publication statusPublished - 2011
Publication categoryResearch
EventInternational Desalination Association (IDA) World Congress, 2011 - Perth Convention Exhibition Centre , Perth, Australia
Duration: 2011 Sep 42011 Sep 9


ConferenceInternational Desalination Association (IDA) World Congress, 2011