Numerical computation of turbulent gas-particle flow in a 90 degree bend: comparison of two particle modelling approaches

Abstract

A numerical study into the physical characteristics of dilute gas-particle flows over a square-sectioned $90^\circ$~bend is reported. Two approaches, namely the Lagrangian particle tracking model and Eulerian two fluid model are employed to predict the gas-particle flows. Renormalization Group based $k$-$\epsilon$ model is used as the turbulent closure for both the approaches; however, for the Eulerian model, additional transport equations are solved to account for the combined gas-particle interactions and the turbulence kinetic energy of the particulate phase. In comparison to both Eulerian-Eulerian and Eulerian-Lagrangian approaches the former was found to yield closer agreement with the measured values. The Eulerian-Lagrangian approach obtains finer details of the behaviour of particles, while Eulerian-Eulerian model can be used for industrial scale problems. All the simulated results are compared against the experimental finding of Kliafas and Holt (1987). References

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