Numerical investigation of flow upstream of a circular cylinder mounted vertically over a flat plate with gap

Abstract

Flow field in the plane of symmetry upstream of circular cylinder mounted perpendicular to a flat plate with varying gap between the cylinder tip and the flat plate is numerically investigated. The results were compared with an experimental study of the configuration. The existence of a multiple vortex system with characteristics similar to that of end-wall flows of surface-mounted obstacles with zero gap was captured by the numerical method. The influence of gap size and Reynolds numbers was also investigated. The results were in good comparison with the experimental data. It has been found that the vortex system structure depends on the free stream Reynolds number; and an increase in the tip gap size caused a shift in the location of vortex system and bifurcation streamline due to increased tip gap flow.

Keywords

Vertically mounted cylinder vortex structure system horseshoe vortex tip gap flow computational fluid dynamics

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