Chemically reacting hypersonic flows over 3D cavities: flowfield structure characterisation

Rodrigo C. Palharini, Thomas J. Scanlon, Craig White

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

In this paper, a computational investigation of hypersonic rarefied gas flows in the transitional flow regime over 3D cavities is carried out by using the direct simulation Monte Carlo method. Such cavities give rise to geometric discontinuities that are often present at the surface of reentry vehicles. This work is focused on the flowfield structure characterisation under a rarefied environment and in the presence of chemical reactions. The cavities are investigated with different length-to-depth ratios, and the different flow structures are studied. In particular, for length-to-depth ratios of 1 and 2, a single recirculation is observed inside the cavities and the main flow is not able to enter the cavity due to the recirculation structure and high particle density. In the case of length-to-depth ratio 3, the flow is able to partially enter the cavity resulting in an elongated recirculation and the beginning of a secondary recirculation core is noticed. For the case of values 4 and 5, the main flow is able to penetrate deeper into the cavities and two recirculation zones are observed; however, for the length-to-depth ratio 5 the flow impinges directly on the bottom surface, which is a behaviour that is only observed in the continuum regime with a cavity length-to-depth ratio greater than 14.
LanguageEnglish
Pages173-187
Number of pages15
JournalComputers and Fluids
Volume165
Early online date31 Jan 2018
DOIs
Publication statusPublished - 30 Mar 2018

Fingerprint

Hypersonic flow
Reentry
Hypersonic aerodynamics
Flow structure
Flow of gases
Chemical reactions
Monte Carlo methods

Keywords

  • cavity flows
  • DSMC
  • rarefied gas
  • thermal protection system
  • reentry

Cite this

Palharini, Rodrigo C. ; Scanlon, Thomas J. ; White, Craig. / Chemically reacting hypersonic flows over 3D cavities : flowfield structure characterisation. In: Computers and Fluids. 2018 ; Vol. 165. pp. 173-187.
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Chemically reacting hypersonic flows over 3D cavities : flowfield structure characterisation. / Palharini, Rodrigo C.; Scanlon, Thomas J.; White, Craig.

In: Computers and Fluids, Vol. 165, 30.03.2018, p. 173-187.

Research output: Contribution to journalArticle

TY - JOUR

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T2 - Computers and Fluids

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AU - Scanlon, Thomas J.

AU - White, Craig

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