6533b873fe1ef96bd12d44cb

RESEARCH PRODUCT

Linear stability analysis of gas-fluidized beds for the prediction of incipient bubbling conditions

Lucio RizzutiG. VellaGiorgio MicaleAntonio Busciglio

subject

Stability criterionSettore ING-IND/26 - Teoria Dello Sviluppo Dei Processi ChimiciWork (thermodynamics)Gas fluidization Stability criterion Mathematical modellingSettore ING-IND/25 - Impianti ChimiciGeneral Chemical EngineeringGeneral ChemistryState (functional analysis)MechanicsStability (probability)Industrial and Manufacturing EngineeringMATHEMATICAL MODELLINGClosure (computer programming)Control theoryEnvironmental ChemistryParticleSensitivity (control systems)FluidizationGas fluidizationMathematicsLinear stability

description

Abstract This work focuses on the development of a novel linear stability criterion for the state of homogeneous fluidization regime, based on a new mathematical model for gas-fluidized beds. The model is developed starting from the well-known particle bed model. A mono-dimensional momentum balance is derived leading to a set of equations which explicitly include voidage-gradient dependent terms (elastic force) for both solid and fluid phases. A fully predictive criterion for the stability of homogeneous fluidization state is here proposed, based on the well-known Wallis’ linear stability analysis. The criterion requires the choice of an appropriate averaging distance, which in the present development is found to be bed-voidage dependent. The linear stability criterion resulted in turn in a simple, yet fully predictive, relationship for incipient bubbling voidage. Validation was carried out analyzing the influence of all physical properties and sensitivity to closure relations, showing substantial agreement with literature data.

https://doi.org/10.1016/j.cej.2009.12.040