Experiments have been carried out to analyse the characteristics of liquid suspensions which exhibit a non-uniform solid concentration. In order to investigate the bed behaviour, a new probe was developed and tested to measure the instantaneous concentration of solid particles. Attention is focused on slugging solid-liquid fluidized beds, where regions of low solid concentration alternate with regions of high solid concentration. The analysis of the results allowed some relevant flow characteristics (slug frequencies and slug velocities) to be recognized.
Di FeliceR.Hydrodynamics of liquid fluidisation. Chem. Engng Sci., 1995, 50, 1213–1245.
2.
WallisG. B.One-dimensional waves in two-component flow (with particular reference to the stability of fluidized beds). Report AEEW-R, United Kingdom Energy Authority, 1962.
3.
FossaM.Design and performance of a conductance probe for measuring the liquid fraction in two-phase gas—liquid flows. J. Flow Measmt Instrum., 1998, 9, 103–109.
4.
BegovichJ. M.WatsonJ. S.An electroconductivity technique for the measurement of axial variation of holdups in three-phase fluidized beds. Am. Inst. Chem. Engrs J., 1978, 24 (2), 351–354.
5.
TsochatzidisN. A.KarapantiosT. D.KostoglouM. V.KarabelasA. J.A conductance method for measuring liquid fraction in pipes and packed beds. Int. J. Multiphase Flow, 1992, 5, 653–667.
6.
FossaM.GuglielminiG.The role of a pipe contraction on the gas—liquid distribution in horizontal intermittent flows. In International Conference onTwo-Phase Flow Modelling and Experimentation, Pisa, Italy, 1999, pp. 763–770.
7.
BruggemanD. A. G.Calculation of different physical constants of heterogeneous substances. Annls Phys., 1935, 24, 636–642.
8.
Saiz-JabardoJ. M.BouréJ. A.Experiments on void fraction waves. Int. J. Multiphase Flow, 1989, 15, 483–493.
9.
NoorergraafI. W.VandijkA.van den BleekC. M.Fluidisation and slugging in large-particle systems. Powder Technol., 1987, 52, 59–68.
10.
GibilaroL. G.FoscoloP. U.RapagnàS.SergeevY. A.Di FeliceR.Fundamentals of slugging fluidisation. In Fluidization IX (Eds FanL. S.KnowltonT.), 1998 (Engineering Foundation, New York).
11.
FoscoloP. U.GibilaroL. G.A fully predictive criterion for the transition between particulate and aggregate fluidization. Chem. Engng Sci., 1984, 39, 1667–1675.
