Experimental Investigation of Drag Coefficient of Two Tandem Cylinders at Staggered Arrangement in Turbulent Flow

In the present study, the effects of turbulent flow are experimentally investigated on the drag coefficient of tandem cylinders with non-equal diameters in different Reynolds numbers. Drag coefficient test for downstream cylinder in diameters A=15.5 mm and B=21.3 mm, was experimentally carried out at two longitudinal distance at five Reynolds numbers based on the upstream cylinder diameter for two turbulence intensity of 4.5 and 7% respectively. The position of the upstream cylinder to the downstream cylinder changes at five angels 0, 22.5, 45, 67.5 and 90 degrees. Results for downstream cylinder in the 4.5% turbulence intensity indicate that with increasing the diameter ratio of the cylinders and increasing the longitudinal distance between the two cylinders, the drag coefficient increases. However, with increasing aligning angels of the upstream cylinder with respect to the downstream cylinder, the drag coefficient varies depending on the nature of flow. Finally, by increasing the flow turbulence intensity, the drag coefficient decreases significantly at all stages of the experiment.