Performance analysis of numerical schemes in highly swirling turbulent flows in cyclones

The aim of this study is to investigate the suitability of various numerical schemes and turbulence models in highly complex swirling flows which occur in tangential inlet cyclones. Three-dimensional steady governing equations for incompressible turbulent flow inside a cyclone were solved numerically using Fluent CFD (computational fluid dynamics) code. The Reynolds stress turbulence model, the Standard κ–ε and the RNG κ–ε turbulence models together with various combinations of numerical schemes are used to obtain axial and tangential velocity profiles, pressure drop and turbulent quantities. Computational results were compared with experimental and numerical values given in the literature, so as to evaluate the performance of the numerical schemes and turbulent models. Comparison of CFD results with experimental data shows that the Reynolds Stress turbulence model yields a reasonably good prediction. Results obtained from the numerical tests have demonstrated that the use of the Presto interpolation scheme for pressure, the Simplec algorithm for pressure–velocity coupling and the quadratic upstream interpolation for convective kinetics (quick) scheme for momentum variables gives satisfactory results for highly swirling flows in cyclones.