The packing limit is not a fixed quantity and may change according to the number of particles present within a given volume and the diameter of the particles. Small particles accumulate in between larger particles increasing the packing limit. For a binary mixture Ansys Fluent uses the correlations proposed by [170].

For a binary mixture with diameters > , the mixture composition is defined as

where

(14–359)

as this is a condition for application of the maximum packing limit for binary mixtures.

The maximum packing limit for the mixture is the minimum of the two expressions (Equation 14–360 and Equation 14–361:

(14–360)

and

(14–361)

The packing limit is used for the calculation of the radial distribution function.

For cases with more than two granular phases, the maximum packing limit (which is used in postprocessing calculations for the mixture phase) is computed as the maximum value of the Packing Limit for each granular phase.