Efeitos de modelos submalha em escoamentos em ciclones

Abstract

A Large-Eddy Simulation (LES) of a single-phase turbulent flow in flat bottom model cyclone geometry was performed. The chosen fluid has the physical properties of air, and the particulate phase was not considered in this work, so the underflow duct was not considered idem, which means that the simulated cyclone has only one output (the overflow duct). The computational code utilized is a dedicated type of code which incorporates the finite volume method using SIMPLE algorithm for the pressure velocity coupling on unstructured threedimensional computational grid. The standard Smagorinsky sub-grid scale model, including Van Driest wall damping function, and Yakhot s RNG sub-grid model were applied. The Simulation was performed at a moderated Reynolds number, and the results for average axial and tangential velocities as well as RMS velocities in these directions show consistent agreement when compared with experimental ones. The LES simulation was run on a PC on a reasonable time frame, suggesting that the application of this accurate methodology is affordable in an industry environment for designing and optimizing cyclones.