hi.

i am using CFX 10. i am working on a problem on cyclone separator which are used for dust seperation from air. i am using the particle transport model. i know the mass flow rate of the continuous fluid i.e. air and that of the dust particles also at inlet. the air and dust may leave from the top or from the bottom outlet... i am setting outlet to ambient (static pressure) for both the outlets. i can calculate mass flow rate of air at both the outlets, almost 95% of incoming air is leaving from the top, and rest from the bottom... but this is not the case with the dust particles, major portion of the dust should leave from the bottom outlet, it might be, but i am just not able to calculate how much that fraction is... can i use the variable "mass flow density" for this calculation??? and what does it exactly means by "mass flow density"???

i want to calculate the dust collection efficiency of the separator, and the pressure drop...

can anyone help???

thanks.

- uday

Modelling cyclones with CFD generally results in inaccurate predictions unless extreme measures regarding turbulence modelling are taken.