PIV measurement study on flow around circular cylinders with low aspect ratio piercing the free surface

摘要

PIV measurements were carried out in a recirculating water channel atthe Reynolds number of 43,000 to understand the three-dimensional flowstructures around the free end of the cylinders with low aspect ratiopiercing the free surface. Flow fields at different vertical and horizontalplanes were presented for two aspect ratios, namely 2.0 and 0.5. Theresults showed the core of the longitudinal recirculation region (bubbles)varied at different planes for aspect ratio 2.0 and did not vary for aspectratio 0.5. The difference of vortices showing up between aspect ratio 2.0and aspect ratio 0.5 was also presented.