
M. H. Gazzah et al. / Natural Science 2 (2010) 635-640
Copyright © 2010 SciRes. OPEN ACCESS
640
the mean velocity decay constant Ku, the spreading rate
2/1
u
S and the centerline value of the velocity fluctuation
intensities has been presented. The predictions agree
reasonably well with the very recent experimental study
in the literature for axisymmetric jets. The major visible
effect of the co-flow is the jet decay rate reduction, in
comparison with the free jet case. However, based on
entrainment definition, it is mainly shown that the co-
flow reduce the air entrainment.
REFERENCES
[1] Panchapakesan, N.R. and Lumley, J.L. (1993) Turbu-
lence measurements in axisymmetric jets of air and hel-
ium, Part 2. Helium jet. Journal of Fluid Mechanics, 246,
225-247.
[2] Ruffin, E., Schiestel, E., Anselmet, F., Amielh, M. and
Fulachier, L. (1994) Investigation of characteristic scales
in variable density turbulent jets using a second-order
model. Physics of Fluids, 6(8), 2785-2799.
[3] Chassaing, P., Harran, G. and Joly, L. (1994) Density flu-
ctuation correlations in free turbulent binary mixing.
Journal of Fluid Mechanics, 279, 239-278.
[4] Lucas, J.F. (1998) Analyse du champ scalaire au sein
d’un jet turbulent axisymétrique à densité variable. Ph.D.
Thesis, Université d’Aix-Marseille II, Marseille.
[5] Gazzah, M.H., Sassi, M., Sarh, B. and Gökalp, I. (2002)
Simulation numérique des jets turbulent subsoniques à
masse volumique variable par le modèle k-ε. Interna-
tional Journal of Thermal Sciences, 41, 51-62.
[6] Imine, B., Saber-Bendhina, A., Imine, O. and Gazzah, M.H.
(2005) Effects of a directed co-flow on a non-reactive
turbulent jet with variable density. International Journal
of Heat and Mass Transfer, 42(1), 39-50.
[7] Gazzah, M.H., Belmabrouk, H. and Sassi, M. (2004) A
numerical study of the scalar field in turbulent round jet
with co-flowing stream. Computational Mechanics, 34(5),
430-437.
[8] Gazzah, M.H., Belmabrouk, H. and Sassi, M. (2005)
Scalar transport modelling in turbulent round jets with
co-flowing stream. International Journal of Thermal Sci-
ences, 44(8), 766-773.
[9] Borean, J.L., Huilier, D. and Burnage, H. (1998) On the
effect of a co-flowing stream on the structure of an axi-
symmetric turbulent jet. Experimental Thermal and Fluid
Science, 17(1-2), 10-17.
[10] Schefer, R.W. and Dibble, R.W. (2001) Mixture fraction
field in a turbulent non-reacting propane jet. American
Institute of Aeronautics and Astronautics Journal, 39(1),
64-72.
[11] Antoine, Y
., Lemoine, F. and Lebouché, M. (2001) Tur-
bulent transport of a passive scalar in a round jet dis-
charging into a co-flowing stream. European Journal of
Mechanics - B/Fluids, 20(2), 275-301.
[12] Hakem, M., Hazzab, A. and Ghenaim, A. (2007) Ex-
perimental investigation of elliptical jet in coflow. Inter-
national Journal of Applied Engineering Research, 2(1),
31-43.
[13] Wang, P., Fröhlicha, J., Michelassib, V. and Rodi, W.
(2008) Large-eddy simulation of variable-density turbul-
ent axisymmetric jets. International Journal of Heat and
Fluid Flow, 29(3), 654-664.
[14] Curtet, R. (1957) Contribution à l’étude théorique des
jets de revolution. Extrait des Comptes rendus de l’Aca-
démie des Sciences, 244, 1450-1453.
[15] Steward, F.R. and Gurus, A.G. (1977) Aerodynamic of a
confined jet with variable density. Combustion Science
and Technology, 16(1-2), 29-45.
[16] Djeridane, T. (1994) Contribution à l’étude expérimentale
de jets turbulents axisymétriques à densité variable. Ph.D.
Thesis, Université d’Aix-Marseille II, Marseille.
[17] Schiestel, R. (1993) Modélisation et simulation des
écoulements turbulents. Hermès Group, Paris.
[18] Patankar, S.V. (1980) Numerical heat transfer and fluid
flow. Hemisphere Publishing, Washington, D.C.
[19] Laufer, J. (1953) The structure of turbulence in fully
developed pipe flow. National Advisory Committee for
Aeronautics–Report–1174, 417-434.
[20] Chen, C.J. and Rodi, W. (1980) Vertical turbulent buo-
yant jets—a review of experimental data. The Science
and Application of Heat and Mass Transfer, Pergamon
Press, New York.
[21] Gharbi, A., Ruffin, E., Anselmet, F. and Schiestel, R.
(1996) Numerical modelling of variable density turbulent
jets. International Journal of Heat and Mass Transfer,
39(9), 1865-1882.
[22] Sanders, J.P.H., Sarh, B. and Gökalp, I. (1997) Variable
density effects in axisymmetric isothermal turbulent jets:
a comparison between a first-and a second-order turbu-
lence model. International Journal of Heat and Mass
Transfer, 40(4), 823-842.