Near and Far-Field Analysis of an Axisymmetric Fractal-Forced Turbulent Jet

  • Massimiliano BredaEmail author
  • Oliver R. H. Buxton
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 196)


In this paper, the role of the initial conditions in affecting the flow physics in the near-field, and the evolution towards self-similarity, of an axisymmetric turbulent jet is examined. The near-field large scale coherent structures are manipulated with the aid of noncircular geometries, such as square and fractal exits. Planar PIV and hot-wire anemometry are deployed to study the flow both spatially and temporally. Despite the significant alteration of the near-field flow physics due to the different exit geometries, it is found that the evolution towards self-similarity is comparable between all jets. Moreover, non-equilibrium dissipation is found between 24 and 26 equivalent diameters \(D_e\) downstream of the jet exit where mean velocity and Reynolds stresses are self-similar, suggesting the microscales of the flow take much further than previously thought to regain the classical scaling laws.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Imperial College LondonLondonUK

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