Flow Characteristics around Rotating Circular Cylinder with Arc Grooves
Details
This paper describes flow characteristics around rotating circular cylinder with arc grooves. In this study, thirty-two arc grooves set on die cylinder surface, and the groove depth changes to three types. The pressure of cylinder surface is measured, and the wake of the circular cylinder with grooves is measured by hot-wire anemometer. The drag and lift coefficients are calculation from this pressure distribution. In the case of smooth cylinder, the drag coefficient and the lift coefficient decreases at α=0.3 in Re=1.2×10^5, and the lift coefficient has negative value at α=0.5. In the case of circular cylinder with grooves, the drag coefficient increases as α increases, and the lift coefficient increases monotonously, too. As grooves depth becomes deeper, the drag coefficient does not influence for α increases, and the increasing inclination of the lift coefficient becomes small. These phenomena have a connection with the change of Karman vortex range.
