A univalent spiral-vortex model for separated flow past a polygonal obstacle

  • Piero Bassanini
  • Alan Elcrat
Original Papers


A free-streamline flow model for flow past a polygonal obstacle with a near-wake terminating in Tulin's double spiral vortices is constructed. The flows are univalent for a large class of geometries. In addition a criterion is given for determining the underpressure as function of the Reynolds number using the Stokes solution for diffusion of a vortex sheet, and an extension of Tulin and Hsu's matching theory to transitional flows.


Vortex Reynolds Number Alla Mathematical Method Large Class 


Si costruisce un modello di flusso con scia e vortici a doppia spirale alla Tulin per un ostacolo poligonale arbitrario. Il flusso risulta univalente per un' ampia classe di geometrie. Inoltre viene proposto un criterio per correlare il parametro del modello al numero di Reynolds del corrispondente flusso viscoso, combinando la soluzione di Stokes per la diffusione di uno strato di vortici con la teoria di Tulin e Hsu (1980).


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Copyright information

© Birkhäuser Verlag 1988

Authors and Affiliations

  • Piero Bassanini
    • 1
  • Alan Elcrat
    • 2
  1. 1.Dipartimento di MatematicaUniversità di Roma “La Sapienza”RomaItaly
  2. 2.Dept. of Mathematics/StatisticsWichita State UniversityWichitaUSA

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