logo  Narasimha Mangadoddy
Ph.D., JKMRC, University of Queensland
M.Tech., IIT Kanpur

Computational Fluid Dynamics, or CFD, uses advanced computer software to model the flow of fluids through a processing facility. The fluid may be in liquid, gas or solid form, or a combination of them. Using computer simulation a wide range of variations in physical design and operational parameters can be tested and refined until a set which gives optimum performance is identified. The broad application of CFD to new and existing plant in the chemical industries, mineral processing, metal production and energy industries has the potential to save companies many millions of dollars per year.

In recent years, our focus research has been to develop and validate the multi-phase CFD models for various mineral processing units like dense medium cyclones (DMC), hydrocyclones (HC), feed slurry distributors and flotation devices. In particular, extensive results have been obtained on the detailed multi-phase flow in DMC/HC devices in terms of air-core resolution, mean and turbulence flow field analysis, turbulent dispersion analysis w.r.to particle classification and understanding the classification mechanism. Extensive CFD validation is also carried out by using the data collected by adopting various experimental techniques; LDA used for the measurement of mean and turbulent flow field, Gamma ray tomography(GRT)/Electrical resistance tomography (ERT) used for the measurement of solids concentration and air-core profiles, physical cyclone experiments used for quantifying the fish hook effect of hydrocyclones at fine size fractions, sampling probe for the collection of solids distribution inside a cyclone, Dubex/ RHEOLOGICA/Tube viscometers used for the characterization of mineral slurries viscosities.

Further these CFD multi-phase models were used to design the new efficient separation equipments for example a TATA-JK dense medium cyclone for treating the fine coal (-2 +0.25mm) having high NGM (near gravity materials) in a collaboration with JKMRC, University of Queensland and a new feed distributor for the TATA Steels coal preparation plant having gravity feeding to DM Cyclones. Improved mathematical models based on industrial historical data and inputs from CFD are also developed using non-linear model building methods for hydrocyclones, which would be part of JKSimMet newer version of mineral processing simulator. Also working on waste utilization/recovery of mineral matter from low grade minerals like low grade iron ore/iron ore slimes through innovative/novel mineral beneficiation research.

ERT
Air-core formation in 350mm DMC

ERT
Flow in a Ball mill