ABSTRACT The effects of a co-flow on a spreading and entrainment rate of turbulent round jets have been studied numerically. The first and second order closure models are used and have been comp- ared with existing experimental data. The influence of theses models on the dynamic fields is examined. The results of the models in general agree well with the trends observed experiment- tally. The co-flowing imposed noticeable restri- ctions on the spreading and the turbulent mixing. Finally, an entrainment hypothesis has been introduced to describe the development of turbulent jets issuing into a stagnant or co-flowing air. It relates the mass flow rate of the surround- ing fluid entrained into the jet to the characteristic velocity difference between the jet and the co-flow. It is obvious that the co-flow decreases considerably the entrainment of air.
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Gazzah, M. , Boughattas, N. , Belmabrouk, H. and Said, R. (2010) The dynamic field in turbulent round jet discharging into a co-flowing stream. Natural Science, 2, 635-640. doi: 10.4236/ns.2010.26079.
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