Author(s): A. M. Ricardo; R. M. L. Ferreira
Keywords: No keywords
Abstract: ABSTRACT: Flow around multiple cylinders in squared or staggered configurations have received considerable attention but random distributions of cylinders are less studied. The main objective is the study of the vorticity fluxes in a flow where turbulence is generated by randomly placed cylinders. To achieve this goal a flow around an isolated cylinder and a flow within a random array of cylinders were experimentally tested. The experimental databases were acquired with a 2D Particle Image Velocimetry system (PIV) with a spatial resolution that allows the computation of vorticity fields and vorticity fluxes. Results show an accentuated decrease of the longitudinal vorticity flux in the wake of cylinders within dense arrays, confirming the existence of vorticity cancellation mechanisms. The strong longitudinal vorticity flux reduction in dense patches is not accompanied by an increase of the lateral flux of vorticity across the symmetry axis of the cylinders.