INTERACTIVE FLOW AROUND 2 CIRCULAR-CYLINDERS OF DIFFERENT DIAMETERS AT CLOSE PROXIMITY - EXPERIMENT AND NUMERICAL-ANALYSIS BY VORTEX METHOD

Experimental investigations and numerical analysis were carried out to clarify the behavior of an interactive flow around two circular cylin ders with different diameters. In particular, the reattachment that th e separated shear layer from the main cylinder reattaches on the rear surface by Coanda effect was noted. The results obtained were as follo ws. Intermittency of the reattachment was found in the present numeric al calculation, and was confirmed experimentally. The calculated value s of time-averaged fluid forces agreed well with those of experiments, and the qualitative characteristics of calculated Strouhal numbers we re coincident with those of experiment.