FLOW AROUND A SQUARE PRISM AND A CIRCULAR CYLINDER IN TANDEM ARRANGEMENT


Akansu Y. E., YAVUZ T., SARIOĞLU M.

International Conference on Experimental Fluid Mechanics, Liberec, Czech Republic, 24 - 26 November 2010, pp.30-40 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume:
  • City: Liberec
  • Country: Czech Republic
  • Page Numbers: pp.30-40
  • Karadeniz Technical University Affiliated: Yes

Abstract

Aerodynamic characteristics of flow around two bluff bodies of square and circular section in a tandem arrangement have been investigated experimentally at a Reynolds number of 2.2 x 10(4). Experiments were carried out in a wind tunnel for the various values of distance between the bodies in the range of 1 <= L/D <= 10. The upstream square prism side length and downstream circular cylinder diameter were equal to 25 mm. By using pressure transducer and hot-wire anemometer, mean pressure distributions and vortex-shedding from the square prism and circular cylinder were examined. Drag and lift coefficients were obtained from the integration of the pressure distributions. The Strouhal numbers of the test models were determined from the frequency analysis of the velocity fluctuations. A single smoke-wire was set in front of the bodies and the flow structure at the mid-span of test section was visualized at Re=7.0x10(3). Depending on the distance between the bodies, the positions of flow attachments, separations, reattachments and the structures of the vortex formation region have been clearly obtained from the flow visualization. According to the results, there are three basic flow structures in the case of the two tandem body arrangement depending on the distance between the bodies. These are "pattern I: single body behavior", "pattern II: shear layer reattachment" and "pattern III: vortex shedding between two bodies".