PSEUDO-SOLITONS IN FLUIDIZED-BEDS

An equation to describe a weakly unstable region of a uniformly fluidi zed bed in both gas solid mixtures and liquid-solid mixtures is derive d from a two-fluid model by applying the reductive perturbation method . Our reduced equation near the transition point from stable fluidized beds to unstable ones is the Korteweg-de Vries equation. When the sta te is away from the critical point the effects of dissipations become important. The validity of our reduced equation has been confirmed by our numerical simulation.