Direct numerical simulations of transitional supersonic base flows

Richard D. Sandberg, Hermann F Fasel

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Transitional supersonic base flows at M = 2.46 are investigated using direct numerical simulations. Results are presented for Reynolds numbers based on the cylinder diameter ReD = 3 × 104-1 × 105. As a consequence of flow instabilities, coherent structures develop that have a profound impact on the global flow behavior. Simulations with various circumferential domain sizes are conducted to investigate the effect of coherent structures associated with different azimuthal modes on the mean flow, in particular on the base pressure, which determines the base drag. Temporal spectra reveal that frequencies found in the axisymmetric mode can be related to dominant higher modes present in the flow. It is shown that azimuthal modes with low wave numbers cause a flat base pressure distribution and that the mean base pressure value increases when the most dominant modes are deliberately eliminated. Visualizations of instantaneous flow quantities and turbulence statistics at ReD = 1 × 105 show good agreement with experiments at a significantly higher Reynolds number. For these investigations, a high-order-accurate compressible Navier-Stokes solver in cylindrical coordinates developed specifically for this research was used.

Original languageEnglish (US)
Pages (from-to)848-858
Number of pages11
JournalAIAA Journal
Volume44
Issue number4
DOIs
StatePublished - Apr 2006

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Direct numerical simulation
Reynolds number
Pressure distribution
Drag
Turbulence
Visualization
Statistics
Experiments

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Direct numerical simulations of transitional supersonic base flows. / Sandberg, Richard D.; Fasel, Hermann F.

In: AIAA Journal, Vol. 44, No. 4, 04.2006, p. 848-858.

Research output: Contribution to journalArticle

Sandberg, Richard D. ; Fasel, Hermann F. / Direct numerical simulations of transitional supersonic base flows. In: AIAA Journal. 2006 ; Vol. 44, No. 4. pp. 848-858.
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