2D PIV/PTV–3D uRANS RSM Investigation on the Combined Effect of Iron Filings Filtering Techniques in a Backward Facing Step Flow

Abstract

AbstractThe presence of suspended particles in liquid fluids is one of the main reasons for hydraulic system failure. Metallic impurities in particular increase the presence of toxic substances in wastewater; therefore, it is vital to study and address the behaviour of such particles in water flows. The current literature lacks studiees approaching the combined effect of different filtering techniques in backward-facing step (BFS) flows. This work aims to analyse the behaviour of iron filings within a BFS system, making use of a combined experimental 2D PIV/PTV–3D uRANS computational approach. Experiments and computations are performed at a Reynolds number $$\mathrm{{Re}}_{H} = 3684.63$$ Re H = 3684.63 . Computational measurements are performed in several planes whereas the experimental campaign is focused on the dynamics of the particles through the streamwise middle plane. A half plane reattachment length of $$X_{\rm{r}} = 11.73h$$ X r = 11.73 h is measured for an inlet flow turbulence intensity of about 1%. The trajectories of the iron filings under the influence of an external magnetic field are examined. A comparison with their paths under the influence of no attractive forces elucidates that the presence of an external magnetic field alters their elliptical trajectories. Moreover, a more forward magnet placement reveals greater trajectory disruptions.