GLOBAL OPTIMIZATION OF REVERSE-FLOW GAS CYCLONES: APPLICATION TO SMALL-SCALE CYCLONE DESIGN

Abstract

This paper addresses the optimum design of reverse-flow gas cyclones through the solution of 2 numerical nonlinear optimization problems that respectively maximize cyclone collection and an efficiency/cost ratio. The simulation model was based on the predictive properties of the 1998 finite diffusivity model of Mothes and Löffler, in which the particle turbulent dispersion coefficient is estimated through an empirical correlation between the radial Peclet and Reynolds numbers. The optimizations were formulated with constraints on pressure drop, saltation velocity, and geometrical considerations such that feasible cyclones could always be obtained. The two geometries, named RS_VHE and RS_K, are different from available high-efficiency designs and represent reverse-flow cyclones with a predicted, significantly improved performance. The geometry RS_VHE was built and tested on a laboratory scale, providing experimental evidence of a significantly improved design.

Keywords:

• Gas cyclones
• Optimization
• Turbulent dispersion

ACKNOWLEDGMENTS

The authors thank Fundação para a Ciência e a Tecnologia for financial support through contract PRAXIS/P/EQU/12003/98.