Numerical study of hypersonic flows over reentry configurations with different chemical nonequilibrium models

Jiaao Hao, Jingying Wang, Chunhian Lee

Research output: Journal article publicationJournal articleAcademic researchpeer-review

45 Citations (Scopus)

Abstract

Effects of two different 11-species chemical reaction models on hypersonic reentry flow simulations are numerically investigated. These two models were proposed by Gupta (1990) and Park (1990) [12,15], respectively. In this study, two typical configurations, the RAM-C II vehicle and FIRE II capsule, are selected as test cases, whose thermo-chemical nonequilibrium flowfields are computed by a multi-block finite volume code using a two-temperature model (a translational-rotational temperature and a vibrational-electron-electronic temperature). In the RAM-C II case, it is indicated that although electron number density distributions of the two reaction models appear in a similar trend, their values are distinctively different. Results of the Gupta's model show a better agreement with the electrostatic probe data, while those of the Park's model are more consistent with the reflectometers data. Both models give similar temperature distributions. In the FIRE II case, the two models yield significantly different distribution profiles of ions and electrons, whose differences could reach an order of magnitude. In addition, an abnormal nonequilibrium relaxation process in the shock layer is found in the FIRE II flowfield simulated by the Gupta's model, which proves to be a consequence of electron impact ionization reactions.

Original languageEnglish
Pages (from-to)1-10
Number of pages10
JournalActa Astronautica
Volume126
DOIs
Publication statusPublished - 1 Sep 2016
Externally publishedYes

Keywords

  • Chemical reaction model
  • Hypersonic
  • Thermal nonequilibrium

ASJC Scopus subject areas

  • Aerospace Engineering

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