ABSTRACT
The present study focuses on the effects of the aspect ratio of a rectangular cylinder and the gap height from the ground to the unsteady wake fields around the rectangular cylinder near the ground. The results indicate that the vortex begins to shed by the interaction of the separated shear layer on the upper surface of the cylinder with the upwash flow in the gap region. Based on this investigation, simple passive control methods consisting of attached vertical or horizontal plates on the lower surface of the rectangular cylinder are introduced to reduce the aerodynamic drag as well as to suppress the vortex-induced oscillation.
Acknowledgments
The authors thank “Brain Korea 21 project,” and would like to acknowledge support from the Korea Institute of Science and Technology Information (KISTI) under “The Sixth Strategic Supercomputing Support Program.” The use of the computing system of the Supercomputing Center is also greatly appreciated.