Vortex Structures in the Wake of Inclined Cylinders

In this experimental study, vortex structures in the wake of inclined slender cylinders’ tip have been investigated. Thin cylinders of various diameters between 0.5 mm to 3.5 mm with large aspect ratios ( >> 1) have been exposed to low Reynolds number (Re) flow starting from Re = 150 to 2000. The cylinders were mounted at an angle of attack “” which was varied from 30 0 to 90 0 . Vortex shedding frequencies in conjunction with associated Strouhal numbers of the vortices behind the inclined cylinder have been studied which increased from 0.9 to 1.15 as the angle of attack was decreased from 60 0 to 30 0 , and remained nearly constant to the change of Reynolds number. It was also found that these vortices were very stable at low Re<700 and vanished quickly at high Re>1000. In addition, the stability of these vortices is also dependent on the angle of attack. It was found that these vortices were very sharp and stable at  = 45 0 and started becoming unstable as the angle of attack increased or decreased from 45 0 .