16.5.6 Maximum Packing Limit in Binary Mixtures

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 [ 90].

For a binary mixture with diameters $d_{1}>d_{2}$, the mixture composition is defined as $X_{1} = \frac{\alpha_1}{\alpha_1 + \alpha_2}$

where

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

The maximum packing limit for the mixture is given by

$$\alpha_{s,max} = (\alpha_{1,max} - \alpha_{2,max} + [1 - \sqrt{\frac{d2}{d1}}](1-\alpha_{1,max})\alpha_{2,max} )$$ (16.5-78)

$$* (\alpha_{1,max}+(1-\alpha_{1,max})\alpha_{2,max}) \frac{X_{1}}{\alpha_{1,max}}$$

$$+ \alpha_{2,max}$$ (16.5-79)

otherwise, the maximum packing limit for the binary mixture is

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