CFD simulation of cross-flow mixing in a packed bed using porous media model and experimental validation
Tóm tắt
Understanding the flow pattern of the gas jet can have considerable significance in improving the reactor design and process optimization. The current study attempts to demonstrate the viability of using computational fluid dynamics (CFD) as a design tool for such packed beds by visualizing the flow structure in the reaction zone; the porous media model (PMM) is introduced as a method for simulation of counter-flow single-shaft kilns and parallel-flow regenerative-shaft kilns. The influence of different turbulence models and percent of the turbulence intensity are simulated. The validation of simulations with experimental results is done by the sample dimension of a packed bed in workshops by injecting two gases into the packed bed. The particles are packed by an arrangement named body-centered cubic. However, a few experiments carried out refer to cross-flow injections. The experimental packed bed is 0.62 m long, 0.36 m wide and 0.6 m high. The distribution of oxygen (volumetric ratio of 0.1) is measured at five points at 0.46 m height of the packed bed. The results reveal that the CFD simulation using the PMM is reasonably accurate with respect to the experimental results in all cases.
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