Modeling two-phase gas-solid flow in axisymmetric diffusers using cut cell technique: an Eulerian-Eulerian approach

Abstract

Abstract Axisymmetric diffusers find wide applications in various industrial processes, including combustion systems, pneumatic conveying, and fluidized bed reactors. Understanding and accurately modeling the behavior of two-phase flows in these devices are critical for optimizing their performance and efficiency. Various aspects of the two-phase gas-solid flow, including particle-particle and particle-wall interactions, interphase momentum transfer, and phase segregation, are investigated. Our currently developed technique, which uses a cut-cell technique, is an established new method to handle the inclined wall of an axisymmetric diffuser. The near-wall cells are treated as five faces for the new grid; one is the inclined wall. This helps treat the boundary condition at the wall in an accurate physical way. The code FORTRAN, developed in-house, was used to solve the axisymmetric diffuser using a cut-cell technique. The results of this study will provide valuable insights into the behavior of gas-solid two-phase flows in axisymmetric diffuser. A parametric study of the impact of particles diameters ( 100 , 200 , and 300 μ m $100,\ 200,\ \text{and} \ 300\mu m$ ), the solid volume loading ratios ( 0.005 , 0.008 , 0.01 ) $(0.005,\ 0.008,\ 0.01)$ , and cant angle ( 4.5 ∘ , 7 ∘ , 9.5 ∘ ) $(4.5^{\circ},\ 7^{\circ},\ 9.5^{\circ}) $ effect of axisymmetric diffuser on the local skin friction, pressure, velocity, turbulent kinetic energy, and separation zone.

Keywords

• Axisymmetric diffuser
• Eulerian-Eulerian approach
• Turbulent flow
• Finite volume
• RANS
• CFD