Experimental investigations of chaotic hydrodynamic attractors in circulating fluidized beds

Abstract The hydrodynamic behavior of a cold experimental circulating fluidized bed (CFB) has been investigated using deterministic chaos theory. The time series of experimentally measured differential pressure fluctuations along the riser height of a CFB are analyzed. Major frequencies were identified using spectral frequency analysis. Poincare maps of the attractor were constructed and the correlation dimension measured. The hydrodynamic behavior of the CFB appears to be chaotic. The fractal correlation dimension of this chaotic attractor is found to be low, ranging from 1.5 to 1.9, for the fluidizing conditions studied.

[1]  D. Jeffrey,et al.  Kinetic theories for granular flow: inelastic particles in Couette flow and slightly inelastic particles in a general flowfield , 1984, Journal of Fluid Mechanics.

[2]  Prabhu R. Nott,et al.  Frictional–collisional equations of motion for granular materials and their application to flow in aerated chutes , 1992, Journal of Fluid Mechanics.

[3]  S. Savage,et al.  Stresses developed by dry cohesionless granular materials sheared in an annular shear cell , 1984, Journal of Fluid Mechanics.

[4]  R. Jackson,et al.  Gas‐particle flow in a vertical pipe with particle‐particle interactions , 1989 .

[5]  J. Jenkins,et al.  A theory for the rapid flow of identical, smooth, nearly elastic, spherical particles , 1983, Journal of Fluid Mechanics.

[6]  Dimitri Gidaspow,et al.  Dense, vertical gas‐solid flow in a pipe , 1992 .

[7]  Akira Nonaka,et al.  A new similarity rule for fluidized bed scale‐up , 1986 .

[8]  S. Savage.  Streaming motions in a bed of vibrationally fluidized dry granular material , 1988, Journal of Fluid Mechanics.

[9]  Sankaran Sundaresan,et al.  Gas‐solid flow in vertical tubes , 1991 .

[10]  Dimitri Gidaspow,et al.  Hydrodynamics of Fiuidizatlon and Heat Transfer: Supercomputer Modeling , 1986 .

[11]  J. X. Bouillard,et al.  Porosity distributions in a fluidized bed with an immersed obstacle , 1989 .

[12]  D. Gidaspow,et al.  A bubbling fluidization model using kinetic theory of granular flow , 1990 .

[13]  S. Savage.  Instability of unbounded uniform granular shear flow , 1992, Journal of Fluid Mechanics.