CFD modeling of sieve and pulsed-sieve plate extraction columns

摘要

Present work deals with the development of a computational fluid dynamics(CFD)model for understanding the hydrodynamics in sieve and pulsed-sieve plate extraction columns.The model is based on Eulerian-Eulerian approach along with standard k-e model for turbulence.The CFD model has been validated by comparing(i)the height of the accumulated layer of the dispersed phase under the plate,and(ii)hold-up of the dispersed phase on the sieve plates with the corresponding values calculated by the correlations reported by Laddha and Degaleesan [Laddha,G.S.,Degaleesan,T.E.,1976.Transport Phenomena in Liquid Extraction.Tata McGraw Hills Publishing Co.Ltd.,pp.305-330].Model predictions were found to be within ±10%.The validated model has been extended to study the regime transition in pulsed-sieve plate columns.Overall,the developed CFD model is found to be able to predict the hydrodynamic aspects of plate extraction columns: like variation in hold-up above and below the plate,movement of continuous phase across the plate and through the downcomer,different operating regimes at different pulsing velocities,etc.