Some Remarks on CFD in Cyclones

As mentioned, LES seems to be a significant step forward, allowing not only direct simulation of the most important effects of turbulence, but also more direct calculation of the effect of the particles on the tmbulence intensity. 

Significant strides still need to be made, however. Cyclone efficiency depends to a large extent on the behaviour of dense particle strands where the interaction between the particles becomes important, and this is a field where much research still needs to be done and one in which the authors of this book are active. Also, although interesting progess is being made, phenomena such as the vortex end are still not successfully simulated. 

We look forward to seeing the developments of CFD for cyclone modeling in the time to come. 

The drag force between the gas and the particles must still be evaluated by using a model, e.g. by assuming Stokes drag law 

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