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Numerical Analysis of Flow Characterization in a Continuous Crystallizer

Anjana Thimmaiah, Lister Falleiro, Abhishek Naval, Akshat Ambekar, B. Ashraf Ali

Abstract


In this work, hydrodynamics in a draft tube continuous crystallizer is analyzed computationally through Ansys CFD to crystallization phenomena. Hindrance to fluid mixing and particle suspension due to vortexing can be overcome by providing baffles. A draft tube ensures that it directs the flow in vertical direction ensuring good axial blending. Here CFD simulations are performed using multiple reference frame (MRF) with sliding mesh approach in transient condition for flow time of 5s. The flow fields and liquid circulation patterns were modelled using the standard k-ε turbulence model. The flow-field in continuous crystallizer is quantified by calculating time averaged velocityprofiles along the horizontal line and by analyzing the temporal variation of liquid velocity at a point for various flow rates. Further, turbulence in such crystallizer is analyzed for various flow rates. The liquid circulation in such continuous crystallizer is calculated for various flow rates to find an optimal flow rate at which the continuous crystallizer is to be operated, hence to improve overall performance of the crystallizer as it depends both on the mean flow field and on the associated turbulence characteristics.

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