Prediction on immersed tubes erosion using two-fluid model in a bubbling fluidized bed

A numerical study based on a gas–solid two-fluid model using body-fitted coordinates to predict the immersed tube erosion rate in a bubbling fluidized bed has been conducted. Computations have been performed at various s/D ratios (ratio of the spacing between two tube centers to the diameter of the tubes) for a bed into which one, two, three or four immersed tubes were inserted. A monolayer kinetic energy dissipation model is implemented to simulate the erosion on the surfaces of the immersed tubes at the body-fitted coordinates. The effect of the s/D ratios on the erosion rate in the bubbling fluidized bed is investigated. A granular temperature distribution provides an indication of the regions on the immersed tubes that could be susceptible to fluctuation intensity of the solid phase. Wake properties influenced the erosion rate remarkably. Calculated erosion rates on the surfaces of the immersed tubes were in good agreement with previous experimental and numerical findings.

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