Measurements of particle and fluid velocities are reported for a turbulent, liquid-solid, sudden expansion flow flowing in the direction of gravity and laden with solid particles, at loadings equal to 1, 2, 3, 4, and 5 percent per volume. The measured two-phase flow velocities are compared to the characteristics of the corresponding single phase flow. Forces and flow mechanisms affecting particle dispersion in the various flow regimes are identified and it is indicated that there exist regions where the transverse Saffman lift force attains high values and controls particle dispersion. A consistent correlation between the mean reattachment point and the volumetric particle loading is indicated. All the two phase flows examined reattached upstream the corresponding mean reattachment location measured for the single phase flow. Increasing particle concentration affected locally the flow behaviour, with most obvious consequences within the recirculation zone and the near wall region.

1.
Achimastos, Th. J., Dimopoulos, D. A., Klipfel, A. S., and Founti, M. A., 1993, “Investigations on Particle Dispersion in an Axisymmetric Vertical Two-Phase Sudden Expansion Flow,” Proceedings of the 5th International Symposium on Refined Flow Modeling and Turbulence Measurements, Press de l’Ecole National des Ponts et Chausse´es, Paris, pp. 465–475.
2.
Berlemont, A., Benoist, F., and Gouesbet, G., 1994, “Influence of Collisions on Particle Fluctuating Velocities Using a Lagrangian Approach,” ASME, Numerical Methods in Multiphase Flows, Fluids Engineering Division Summer Meeting, Nevada, FED-Vol. 185, pp. 23–28.
3.
Crowe, C. T., 1981, “On The Relative Importance Of Particle-Particle Collision In Gas-Particle Flows,” Proceedings of Conference on Gas Borne Particles, Institute of Mechanical Engineers, C 78/81, pp. 135–137.
4.
Fessler, J., and Eaton, K., 1994, “Particle-Turbulence Interaction In A Backward-Facing Step Flow,” Report No. MD-70, Thermoscienes Division, Department of Mechanical Engineering, Stanford University, Stanford, CA.
5.
Fleckhaus
D.
,
Hishida
K.
, and
Maeda
M.
,
1987
, “
Effect of Laden Solid Particles on the Turbulent Flow Structure of a Round Free Jet
,”
Experiments in Fluids
, Vol.
5
, pp.
323
333
.
6.
Founti, M. A., and Papaioannides, G., 1992, “Influence of Expansion Ratio on the Size of Recirculation Zone in Two-Phase Sudden Expansion Flows,” Proceedings 6th Intern. Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal, pp. 33.1.1–33.1.6.
7.
Founti, M., and Klipfel, A., 1994, “The Shear Lift Effects on the Particle Motion in Two-Phase Sudden Expansion Flows,” ASME, Numerical Methods in Multiphase Flows, Fluids Engineering Division Summer Meeting, Nevada, FED-Vol. 185, pp. 81–92.
8.
Founti
M.
, and
Klipfel
A.
,
1998
, “
Experimental and Computational Investigations of Nearly Dense Two-Phase Sudden Expansion Flows
,”
Experimental Thermal and Fluid Science
, Vol.
17
, Issue
1–2
, pp.
27
36
.
9.
Hardalupas, Y., Taylor, A. M. K. P., and Whitelaw, J. H., 1992, “Particle Dispersion in a Vertical Round Sudden Expansion Flow,” Phil. Transactions of the Royal Society, London A, Vol. 341, pp. 411–442.
10.
Hishida, K., Nakano, H., and Maeda, M., 1989, “Turbulent Flow Characteristics of Liquid-Solid Particle Confined Jet,” International Conference on Mechanics of Two-Phase Flow, National Taiwan Univ., Taiwan, pp. 209–214.
11.
Kaftori, D., Hetsroni, G., and Banerjee, S., 1995, “The Effects of Particles on the Structure of Wall Turbulence,” Proceedings of the 2nd International Conference on Multiphase Flows, Kyoto, 2, PTI, pp. 11–16.
12.
Kenning, V., and Crowe, C. T., 1994, “The Effect of Solids Concentration on Self-Induced Turbulence, in Liquid-Solid Flows,” ASME Fluids Engineering Division, USA. FED-Vol. 189, pp. 71–74.
13.
Nouri
J. M.
,
Whitelaw
J. H.
, and
Yianneskis
M.
,
1987
, “
Particle Motion and Turbulence in Dense Two-Phase Flows
,”
International Journal of Multiphase flow
, Vol.
13
, No.
6
, pp.
729
739
.
14.
Qiu
H.-H.
, and
Sommerfeld
M.
,
1992
, “
A Reliable Method for Determining the Measurement Volume Size and Particle Mass Fluxes Using Phase-Doppler Anemometry
,”
Experiments in Fluids
, Vol.
13
, pp.
393
404
.
15.
Saffman
M.
,
1987
, “
Automatic Calibration of LDA Measurement Volume Size
,”
Applied Optics
, Vol.
26
, pp.
2592
2597
.
16.
Sommerfeld, M., 1989, “Numerical Simulation of the Particle Motion in Turbulent Flow,” 2nd. International Lecture Course on Multiphase Flow, Tokyo, Japan.
17.
Sommerfeld
M.
,
Ando
A.
, and
Wennerberg
D.
,
1992
, “
Swirling, Particle-Laden Flows Through a Pipe Expansion
,”
ASME JOURNAL OF FLUIDS ENGINEERING
, Vol.
114
, pp.
648
656
.
18.
Sommerfeld, M. and Qiu, H.-H., 1990, “Detailed Measurements in a Swirling Particulate Two-Phase Flow by a Phase-Doppler Anemometer,” Proceedings of 5th Workshop on Two Phase Flow Predictions, pp. 15–32, Erlangen.
19.
Sommerfeld, M., and Zivkovic, G., 1992, “Recent Advances in the Numerical Simulation of Pneumatic Conveying Through Pipe Systems,” 1st European Computational Fluid Dynamics Conference, Brussels.
20.
Tsuji
Y.
,
Morikawa
Y.
,
Tanaka
T.
,
Karimine
K.
, and
Nishida
S.
,
1988
, “
Measurements of an Axisymmetric Jet Laden with Coarse Particles
,”
International Journal of Multiphase Flow
, Vol.
14
, pp.
565
574
.
21.
Yanta, W. J., 1973, “Turbulence Measurements with a Laser Doppler Velocimeter,” Report NOLTR-73-94, NOL, White, Oak, Silver Spring, MD.
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