Dye Injection Flow Visualization Around a Rotating Circular Cylinder

Abstract

In this study, the visualization of the flow structure around a circular cylinder was investigated with dye injection experiments. The experiments were carried out in the closed-circuit open water channel in Osmaniye Korkut Ata University. Experiments have been studied on a circular cylinder at different rotational speeds. Experiments were carried out at Re = 1000 according to cylinder diameter and free stream velocity. In the study, with the increase of the rotation speed, an acceleration layer occurs between the fluid velocity in the cylinder wake in the flow direction and the flow from the circumference of the cylinder and the speed of rotation. This situation caused the complete disappearance of the vortex ruptures in the flow direction and the emergence of Kelvin Helmhotz fluctuations. As a result of the study, it is seen that the flow control is insufficient at low rotational speeds, but the flow can be controllable at high rotational speeds.

Keywords

• Dye injection
• Visualization
• Circular cylinder
• Flow control

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