A Nonequilibrium Finite-Rate Carbon Ablation Model for Radiating Earth Re-entry Flows

Abstract

Vehicles entering planetary atmospheres at high speed require an ablative heat shield in order to withstand the high thermal energy flux to the body. Numerical simulations were conducted to investigate the influence of carbon ablation on shock layer radiation. Data collected from experiments performed in the X-2 expansion tunnel at the University of Queensland was used to compare to the simulations. The model was made of isomolded graphite and was tested in 8.5 km/s Earth entry flow. The model surface was heated within a temperature range of 1770-3280 K. The radiation emitted from the CN violet bands was measured by ultraviolet spectrometry in a spectral range from 353-391 nm. This research develops a novel finite-rate surface kinetic model for determining the chemical state of an ablating boundary layer. The ablative gas species predicted by this new model improves agreement with experimental measurements than predictions provided by legacy ablation models, and represents a significant improvement in current modeling capabilities for hypersonic nonequilibrium ablating re-entry flows.

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Document Details

Document Type
Technical Report
Publication Date
Sep 17, 2015
Accession Number
ADA622133

Entities

People

  • Christopher R. Alba

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • C4I
  • Energy and Power Technologies
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Boundary Layer
  • Chemical Reactions
  • Computational Fluid Dynamics
  • Energy
  • Energy Transfer
  • Heat Energy
  • Heat Transfer
  • Measurement
  • Pressure Distribution
  • Rate Of Formation
  • Shock Tubes
  • Surface Chemistry
  • Test Facilities
  • Thermal Conductivity
  • Thermodynamic Properties
  • Thermodynamics

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Molecular Photonics/Laser Physics
  • Thermal Physics or Thermal Science.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flight
  • Hypersonics - Hypersonic Flow