Chemical Engineering Science, Vol.51, No.20, 4639-4647, 1996
Jump Conditions for One-Dimensional 2-Phase Shock-Waves in Fluidized-Beds - The Effect of the Jump in Fluid Pressure
The effect of a fluid pressure discontinuity on the one-dimensional, two-phase jump conditions for a fluidised suspension is evaluated on the basis that the fluid pressure field can be regarded as a function of void fraction alone; this assumption is shown to be valid for the case of a discontinuity travelling between two zones in dynamic equilibrium. The adopted procedure is shown to be fully compatible with the linear analysis, applicable to the case of infinitesimal jumps, and to circumvent the problem of the inadmissibility of non-linear operations in the general jump analysis. For gas fluidisation it is demonstrated that the small fluid pressure discontinuities that can occur have virtually no effect on the other jump characteristics, even for operation at very high pressure; for liquid fluidisation the effect is also generally small, although, for particles of relatively low density and large diameter, the void fraction downstream of a discontinuity can be significantly affected by the jump in fluid pressure.