Turbulent flow around a rotating stepped cylinder

Department of Mechanical Engineering, Inha University, Incheon, Incheon, South Korea
Physics of Fluids (Impact Factor: 2.03). 04/2002; 14(4). DOI: 10.1063/1.1455625
Source: OAI


Direct numerical simulation (DNS) of turbulent flow around a rotating cylinder with two backward-facing steps axisymmetrically mounted in the circumferential direction was performed and compared with DNS of plane backward-facing step flow (PBSF) of Le [J. Fluid Mech. 330, 349 (1997)]. The original motivation of this work stemmed from the efforts to design a simple device which can generate flows of high turbulence intensity at low cost for corrosion researchers. It turned out that the current flow shows flow structures quite similar to those of PBSF downstream of the step, even though configurations of the two flows are totally different from one another. The stepped cylinder appears to be a cost-effective tool in the generation of flow structures similar to those of PBSF. (C) 2002 American Institute of Physics.

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    • "The ratios among the roughness height ℎ, the roughness interval í µí¼†, and the reattachment length í µí°¿ re are also shown. on a turbulent Taylor-Couette flow (TCF) with regular roughness elements (other than DNS for stepped cylinder [13] [14]). As is well known, TCF occurs when fluid is contained between two concentric independently rotating cylinders and often provokes Taylor vortices due to Coriolis instability when the inner cylinder rotates at relatively high speed [15] [16]. "
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