How to define the Aspect Ratio for a non-spherical drag model in CFD-DEM.

Question

I learned from the sieve_base case in Tutorial 6A — Particle Separation in a Harvester, that defining a non-spherical drag model requires defining the Aspect Ratio. However, I am now encountering particles where the length, width, and height are all different, such as elliptical disk-shaped particles or irregular tetrahedral particles. How should I determine and define the values for these.

Stephen Cole · Accepted Answer

Hi,

I'd typically set the aspect ratio as the ratio of the longest dimension to it's shortest dimension based on a bounding box surrounding the particle.

Its an approximation of the drag on the particle, if you have any experimental data you could use this as a parameter to tune the interactions.

Regards

Stephen