PIV Analysis of the Wake behind a Single Tube and a one-Row Tube Bundle: Foamed and Finned Tubes

摘要

The aim of this study is to investigate and compare the wake behind fin and foam covered circular cylinders by mean of Particle Image Velocimetry (PIV). Two different arrangements were examined namely single cylinder and a single-row bundle of three identical cylinders in cross flow. The experiments are conducted for a range of Reynolds numbers from 1500 to 8000 based on the inner cylinders diameter and the air velocity upstream of the bundle. The two dimensional planar PIV results as well as POD analysis show the important effects of the inlet velocity, the foam and fin covers, as well as cylinder arrangement, being an isolated single cylinder or bundled, on the wake. The results show a considerable increase of the wake size by using the foam instead of fin in single tube. The results of this study can be used as an accurate boundary condition to model the flow field past such cylinders.