Bubble Formation for Different Particle Types and Particle Classification in MFiX

MFiX
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Hello MFiX Developers and Community,

I’m working with MFiX for simulating fluidized beds and had a couple of questions I hope someone can help clarify:

  1. How does MFiX calculate or estimate the bubble diameter during a simulation? Is it based on correlations, local flow conditions, or user-defined parameters?

  2. Does MFiX internally determine or classify particle types according to the Geldart classification (A, B, C, D)? Is this something users must infer or set based on particle properties? I ask as there are bubble size correlations applicable to specific particle types (like Geldart B particles, for instance)

Any guidance or references to documentation would be greatly appreciated!

Thanks in advance,
Cam

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  1. MFiX doesn’t compute any bubble diameter directly. With the Two-Fluid-Model, MFiX solves continuous transport equations for the gas and solids phases. Bubbles can be visualized as regions of low solids volume fraction within the bed. To estimate their size, postprocessing of the data is required and is not included in MFiX.
  2. The Geldart classification is not inferred by the code.