Advertisement

Transverse Vorticity Measurements in the Wake of an Inverted Oscillated D-Shaped Cylinder

  • B. Walter
  • M. M. Koochesfahani
  • J. F. Foss
Conference paper
Part of the International Union of Theoretical and Applied Mechanics book series (IUTAM)

Summary

An oscillating inverted D shaped obstruction has been used to provide a well defined vortex street at Reynolds number (U0d/v) equal to 23,000. U0 and d are defined in Fig i which also presents a schematic of the flow based upon phase averaged results.

The purpose of the investigation was to compare time resolved transverse vorticity (ωz(t))measurements with the phase (α) averaged velocity [u(x,y,α),v(x,y,α)] measurements and flow visualization observations. It was expected that the latter two would exhibit good agreement. Prior experience with the ωz(t) measurements in planar shear layers, see Foss (1), has shown that flow fields with a single sign of the mean vorticity (≈∂u/∂y) possess vorticity distributions in which the rms values (ωz) are large with respect to the corresponding mean value. Contrary to this is the plausible expectation that vorticity measurements in the large scale vortex motions would exhibit a clearly recognized distribution during the passage of a large scale coherent motion. The subject flow was selected as a paradigm test to examine the relationships between time resolved vorticity and coherent vortex motions.

Keywords

Shear Layer Wire Array Separate Shear Layer Shaped Obstruction Vorticity Measurement 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. (1).
    Foss, J.F., (1991), “Vorticity Considerations and Planar Shear Layers”, Experimental Heat Transfer, Fluid Mechanics and Thermodynamics ( 1991 ), Ed. Keffer, J.F., Shah, R.K. and Ganic, E.N., Elsevier Co, pp. 240–251Google Scholar
  2. (2).
    Foss, J.F. and Haw, R.C., (1990), “Transverse Vorticity Measurements Using a Compact Array of Four Sensors”, The Heuristics of Thermal Anemometry, ASME-FED, Vol. 97, p 71Google Scholar
  3. (3).
    Walter, B., (1992), “Transverse Vorticity Measurements in the Wake of an Inverted D-shaped Prism”, Dipl.-Ing. Thesis, Rheinisch-Westfälische Technische Hochschule AachenGoogle Scholar
  4. (4).
    Gerrard, J.H., (1966), “The Mechanics of the Formation Region of Vortices Behind Bluff Bodies”, Fluid Mech., Vol. 26, part2, p 401Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • B. Walter
    • 1
  • M. M. Koochesfahani
    • 1
  • J. F. Foss
    • 1
  1. 1.Mechanical Engineering DepartmentMichigan State UniversityUSA

Personalised recommendations