A Linear Stability Analysis of a Homogeneous Fluidized Bed

Authors

  • Y.D. SOBRAL
  • F.R. CUNHA

DOI:

https://doi.org/10.5540/tema.2002.03.02.0197

Abstract

In this work the local equations governing the dynamics of fluidized beds are written in terms of averaged variables and constitutive relations based on physical arguments are proposed. The averaged equations are perturbed with small disturbances from the homogeneous fluidization state, and linearized with respect to the perturbations. A stability analysis is carried out and shows that the particle pressure term has a stabilizing effect and that the particle viscosity acts as a short wave filter. The behavior of the primary instabilities described by the proposed model is in qualitative agreement with experimental observations.

References

[1] T.B. Anderson, R. Jackson, A fluid mechanical description of fluidized beds: Equations of motion, I&EC Fundamentals, 6, No. 4 (1967), 527-539.

G.K. Batchelor, A new theory of the instability of a uniform fluidized bed, Journal of Fluid Mechanics, 193 (1988), 75-110.

T.B. Anderson, R. Jackson, A fluid mechanical description of fluidized beds: Stability of the uniform state of fluidization, I&EC Fundamentals, 7, No. 1 (1968), 12-21.

S.K. Garg, J.W. Pritchett, Dynamics of Gas-Fluidized Beds, Journal of Applied Physics, 46, No. 10 (1975), 4493-4500.

S.E. Harris, D.G. Crighton, Solitons, solitary waves, and voidage disturbances in gas-fluidized beds, Journal of Fluid Mechanics, 266 (1994), 243-276.

J.A. Hernandez, J. Jimenez, Bubble formation in dense fluidized beds, in “Proc. NATO Advanced Research Workshop on the Global Gerentry of Turbulence” (J. Jimenez, ed.), pp. 133-142, 1991.

Y.D. Sobral, F.R. Cunha, A note on the governing equations of fluidized bed suspensions, em “XVI Congresso Brasileiro de Engenharia Mecânica”, vol. 8, 500-509, 2001.

J.F. Richardson, W.N. Zaki, Sedimentation and fluidization, Trans. Inst. Chem. Engrs., 32 (1954), 35-52.

N.A. Frankel, A. Acrivos, Suspensions of non colloidal particles, in “Mobile Particulate Systems”, NATO ASI Series, vol. 287, 57-68, 1995.

K. Anderson, S. Sundaresan, R. Jackson, Instabilities and the formation of bubbles in fluidized beds, Journal of Fluid Mechanics, 303 (1995), 327-366.

G.M. Homsy, M.M. El-Kaissy, A. Didwania, Instability waves and the formation of bubbles in fluidized beds - II, Int. Journal Multiphase Flow, 6 (1980), 305-318.

Published

2002-06-01

How to Cite

SOBRAL, Y., & CUNHA, F. (2002). A Linear Stability Analysis of a Homogeneous Fluidized Bed. Trends in Computational and Applied Mathematics, 3(2), 197–206. https://doi.org/10.5540/tema.2002.03.02.0197

Issue

Section

Original Article