Improvement of Swirl Concentrator

The analysis of a treatment device for pluvial water, proposed by the American Public Works Association (APWA) and called a swirl concentrator, shows that its efficiency greatly depends on a large eddies structure generated by an obstacle placed to obtain a usable hydraulic load-discharge characteristic. The characterization of the convective-diffusive process is done by measuring the transit-time distribution of fluid and liquid particles. The study of similarity law done on two hydraulic models observes the critical velocity of solid particles as similarity parameter. In order to optimize the concentrator efficiency, a configuration of vertical bars is proposed to obtain a flow with a minimum of large eddies structure. A pattern of bar an be added to an already built concentrator with a gain for the removal efficiency.