Abstract
Experimental study was carried out on the vortex breakdown phenomenon in an open cylindrical container with the rotating bottom endwall. Vortex breakdown is seen in certain parameter range of the container aspect ratio H/R and the rotating Reynolds number Re. The working fluid used water-glycerin mixture. The meridional plane of the cylinder was illuminated by fluorescein sodium which is mixed with the working fluid. Velocity map in the meridional plane was measured by using a particle image velocimetry (PIV). Various types of vortex breakdowns were observed. Comparison with the previous experimental and numerical studies is discussed in detail about position of stagnation points, bubble size and differences between present and previous results.