Shukla, S and Govardhan, RN and Arakeri, JH (2013) Dynamics of a flexible splitter plate in the wake of a circular cylinder. In: Journal of Fluids and Structures, 41 . pp. 127-134.
PDF
Jou_Flui_Stru_41_127_2013.pdf - Published Version Restricted to Registered users only Download (570kB) | Request a copy |
Abstract
Rigid splitter plates in the wake of bluff bodies are known to suppress the primary vortex shedding. In the present work, we experimentally study the problem of a flexible splitter plate in the wake of a circular cylinder. In this case, the splitter plate is free to continuously deform along its length due to the fluid forces acting on it; the flexural rigidity (EI) of the plate being an important parameter. Direct visualizations of the splitter plate motions, for very low values of flexural rigidity (EI), indicate periodic traveling wave type deformations of the splitter plate with maximum tip amplitudes of the order of I cylinder diameter. As the Reynolds number based on cylinder diameter is varied, two regimes of periodic splitter plate motions are found that are referred to as mode I and mode II, with a regime of aperiodic motions between them. The frequency of plate motions in both periodic modes is found to be close to the plane cylinder Strouhal number of about 0.2, while the average frequencies in the non-periodic regime are substantially lower. The measured normalized phase speed of the traveling wave for both periodic modes is also close to the convection speed of vortices in the plane cylinder wake. As the flexural rigidity of the plate (EI) is increased, the response of the plate was found to shift to the right when plotted with flow speed or Re. To better capture the effect of varying EI, we define and use a non-dimensional bending stiffness, K*, similar to the ones used in the flag flutter problem, K*=EI/(0.5 rho(UL3)-L-2), where U is the free-stream velocity and L is the splitter plate length. Amplitude data for different EI cases when plotted against this parameter appear to collapse on to a single curve for a given splitter plate length. Measurements of the splitter plate motions for varying splitter plate lengths indicate that plates that are substantially larger than the formation length of the plane cylinder wake have similar responses, while shorter plates show significant differences.
Item Type: | Journal Article |
---|---|
Publication: | Journal of Fluids and Structures |
Publisher: | Elsevier Science |
Additional Information: | Copyright of this article belongs to Elsevier Science. |
Keywords: | Splitter Plate; Cylinder Wake; Vortex Shedding; Strouhal Number |
Department/Centre: | Division of Mechanical Sciences > Mechanical Engineering |
Date Deposited: | 22 Oct 2013 12:05 |
Last Modified: | 22 Oct 2013 12:05 |
URI: | http://eprints.iisc.ac.in/id/eprint/47546 |
Actions (login required)
View Item |