A convective-diffusive reaction zone structure model for turbulent detonations

Matei I. Radulescu, Akiko Matsuo, Chung K. Law

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

The present study examines one-dimensional models for the turbulent reaction zone structure of unstable detonations. Simulations of direct initiation are performed with the postulated reaction zone models and the results are compared with experimental measurements of the critical initiation energy in methane-oxygen-nitrogen detonations. First, it is shown that the assumption of inviscid detonations with homogeneous chemistry leads to over-predictions of the initiation energy by several orders of magnitude. This suggests that turbulent transport in the reaction zone plays an important role. One-dimensional models addressing these effects were investigated. The first model assumed homogeneous chemistry and introduced mass, momentum and energy transport in the governing equations, modeled by the gradient mechanism. In order to recover the correct initiation requirements, the transport terms need to be artificially augmented such that the diffusive time scales are comparable to the convective time scales. In the second model considered, the transport terms are neglected and only the effective activation energy in the one-step Arrhenius model is changed. It is found that the effective activation energy required to capture the correct initiation limits is lower than derived from homogenous ignition chemistry by a factor of ∼5. Detonations with such low activation energies are stable, which correlates well with the global stability of turbulent detonations to external perturbations.

Original languageEnglish
Title of host publicationCollection of Technical Papers - 44th AIAA Aerospace Sciences Meeting
Pages11392-11401
Number of pages10
Volume15
Publication statusPublished - 2006
Event44th AIAA Aerospace Sciences Meeting 2006 - Reno, NV, United States
Duration: 2006 Jan 92006 Jan 12

Other

Other44th AIAA Aerospace Sciences Meeting 2006
CountryUnited States
CityReno, NV
Period06/1/906/1/12

Fingerprint

Detonation
Model structures
detonation
activation energy
Activation energy
chemistry
timescale
energy
ignition
Ignition
momentum
Momentum
Methane
methane
perturbation
Nitrogen
nitrogen
gradients
requirements
oxygen

ASJC Scopus subject areas

  • Space and Planetary Science
  • Aerospace Engineering

Cite this

Radulescu, M. I., Matsuo, A., & Law, C. K. (2006). A convective-diffusive reaction zone structure model for turbulent detonations. In Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting (Vol. 15, pp. 11392-11401)

A convective-diffusive reaction zone structure model for turbulent detonations. / Radulescu, Matei I.; Matsuo, Akiko; Law, Chung K.

Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting. Vol. 15 2006. p. 11392-11401.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Radulescu, MI, Matsuo, A & Law, CK 2006, A convective-diffusive reaction zone structure model for turbulent detonations. in Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting. vol. 15, pp. 11392-11401, 44th AIAA Aerospace Sciences Meeting 2006, Reno, NV, United States, 06/1/9.
Radulescu MI, Matsuo A, Law CK. A convective-diffusive reaction zone structure model for turbulent detonations. In Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting. Vol. 15. 2006. p. 11392-11401
Radulescu, Matei I. ; Matsuo, Akiko ; Law, Chung K. / A convective-diffusive reaction zone structure model for turbulent detonations. Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting. Vol. 15 2006. pp. 11392-11401
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