Abstract

RODRIGUEZ Y DOMINGUEZ, Marcos Matthaeus; ROMERO-MENDEZ, Ricardo; DE LANGE, Dirk Frederik  and  HERNANDEZ-GUERRERO, Abel. Laminar Horseshoe Vortices Upstream of a Short Cylinder Normal to a Flat Plate. Ingenier. mecáni. tecnolog. desarroll [online]. 2011, vol.3, n.6, pp.213-217. ISSN 1665-7381.

A flow visualization experiment was performed in order to characterize the laminar horseshoe vortex system that appears upstream of the ¡unction of a short cylinder and a single flat plate parallel to the flow direction. The experiments were performed in a water tunnel and the technique used for flow visualization was laser illumination of seeded particles whose traces were captured using long exposure photograph. Geometrical and flow parameters, such as Reynolds number and height-to-diameter ratio of the cylinders, are varied during the experiments and the appearance of the flow regimes is determined as a function of these parameters. The behavior of vortex systems is analyzed. Additional to the types of horseshoe vortex systems reported in investigations with tall cylinders, a chaotic type of vortex system was observed for this case. This chaotic horseshoe vortex system occurs only in short cylinders and for sufficiently high Reynolds numbers. Information about the frequency of appearance of periodic vortex systems is presented, from which we could define a cylinder height beyond which the flow behavior becomes independent of height. Information of the position of the main vortex closer to the cylinder and the position of the stagnation point over the cylinder is also reported.

Keywords : Horseshoe vortex; short cylinder; separation effect; chaotic vortex system; periodic behavior.