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Absolute Radiation Measurements in Earth and Mars Entry ConditionsThis paper reports on the measurement of radiative heating for shock heated flows which simulate conditions for Mars and Earth entries. Radiation measurements are made in NASA Ames' Electric Arc Shock Tube at velocities from 3-15 km/s in mixtures of N2/O2 and CO2/N2/Ar. The technique and limitations of the measurement are summarized in some detail. The absolute measurements will be discussed in regards to spectral features, radiative magnitude and spatiotemporal trends. Via analysis of spectra it is possible to extract properties such as electron density, and rotational, vibrational and electronic temperatures. Relaxation behind the shock is analyzed to determine how these properties relax to equilibrium and are used to validate and refine kinetic models. It is found that, for some conditions, some of these values diverge from non-equilibrium indicating a lack of similarity between the shock tube and free flight conditions. Possible reasons for this are discussed.
Document ID
20140008609
Acquisition Source
Ames Research Center
Document Type
Conference Paper
Authors
Cruden, Brett A.
(Engineering Research and Consulting, Inc. Mountain View, CA, United States)
Date Acquired
June 30, 2014
Publication Date
April 7, 2014
Subject Category
Plasma Physics
Fluid Mechanics And Thermodynamics
Report/Patent Number
ARC-E-DAA-TN13965
Meeting Information
Meeting: Radiation and Gas-surface Interaction Phenomena in High-speed Reentry Lecture Series
Location: Urbana-Champaign, IL
Country: United States
Start Date: April 7, 2014
End Date: April 9, 2014
Sponsors: Von Karman Inst. for Fluid Dynamics, North Atlantic Treaty Organization
Funding Number(s)
CONTRACT_GRANT: NAS2-99092
CONTRACT_GRANT: NNA10DE12C
Distribution Limits
Public
Copyright
Public Use Permitted.
Keywords
Radiative Heating
Shock Tube
Entry
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