Role of momentum exchange coefficient in circulating fluidized-bed

The interphase momentum exchange coefficient play an important role in formulating the mathematical description of Circulating Fluidized-Bed (CFB) system. The present study provides a theoretical and numerical investigation and its effects on various parameters. The relevancy of evaluation of interphase momentum transfer and its effect on the voidage profile is discussed. The analyzed numerical result provides a broader perspective for the range of variation of computed data. The results are very near to reality. IPC Code(s): B01J8/24 The performance of the circulating fluidized bed (CFB) system is strongly affected on the dynamics attended within the bed. In CFB the solid particles and the gas are associated with different kinetic energy due to difference in the velocity. The solid particles will possess lower value of kinetic energy due to drag force acting on the solid surfaces. The recent advances treat fluid and solid phase as interpenetrating continuum. This induces exchange of momentum between gas and solid. The two phases penetrate in to each other to exchange momentum and hence at any time the volume fraction of phases must be equal to unity. The estimation of friction between solid and gas particle is vital for numerical solution of the equation of continuity and momentum for solids and gases, which constitute the general approach to Computational Fluid Dynamics (CFD) as given in various publications 1-8 . A complete hydrodynamic description of CFB is still not sufficient to model dense gas solid flow involving Geldart A particles. This significantly limits the use of state-of-the-art CFD techniques in the design and scale-up of fluidized bed reactors like Fluidized Catalytic Crackers (FCC) in petroleum refining. Integral balances are made to develop continuity, momentum and energy balances for both the phases with initial and boundary conditions. Since gas and solids are subjected to different velocity hence, velocity fluctuations are induced. Due to above