A Computational Comparison of Flow and Pressure Fields in Axial and Reverse Flow Cyclone Separators

Yıl 2017, Cilt: 3 Sayı: 2, 20 - 25, 01.11.2017

Ali Sakin

Öz

Cyclones
are separation devices that use centrifugal forces to remove dense phases from
two phase flows. There are many application areas of cyclone separators ranging
from industrial processes to domestic applications due to their simple
structure and lack of movable components. For this reason, they are commonly
preferred where two phase fluid flow accommodated and separation is required.
In this study, axial and reverse flow tangential inlet novel cyclone geometries
were introduced to configure different separation space and to reduce pressure
drop in comparison with traditional cyclone geometry. Although the construction
of a cyclone is simple, the cyclone flow and separation process are very
complex. Therefore, CFD is quite appropriate provided that the proper
mathematical models and computational techniques are used. 3-D and unsteady
governing equations were used for the turbulent cyclone flow. Hexahedral meshed
domain was solved by using Fluent CFD software. Eulerian approach was used to
solve the flow field and transient Reynolds Stress Model (RSM) with the
scalable wall function. Lagrangian approach with DPM (Discrete Phase Model) was
used to calculate discrete phase by releasing particles from inlet surface. CFD
calculations were run for different geometric configurations in order to
analyze performance of cyclones in terms of pressure drop, cut-off diameter and
grade efficiency. Axial and tangential velocity profiles are presented at
defined sections. The computational results of pressure drop, velocity field
and separation efficiency were also compared for the axial and reverse flow
cyclones at the same flow rates.

Anahtar Kelimeler

Pressure drop, CFD

Kaynakça

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