Instability waves and the origin of bubbles in fluidized beds—II Comparison with theory

Abstract

The two-fluid equations describing the motions of isothermal beds are discussed from a continuum mechanics viewpoint. The questions of the invariant form of the relative phase acceleration, the proper description of the “viscosity” of fluidized systems, and the nature of the individual phase pressures are discussed. The linear instability wave problem is formulated and solved and the theory is shown to be capable of describing wave propagation properties measured in an earlier experimental study. The data are then used to deduce values of material constants which are both internally consistent and of reasonable magnitude.