التفاصيل البيبلوغرافية
| العنوان: |
Measurement of Ultraviolet Radiative Heating Augmentation in HIEST Reflected Shock Tunnel |
| المؤلفون: |
Cruden, Brett A, Brandis, Aaron M, Olejniczak, Joseph, Grinstead, Jay, Kirk, Lindsay, Tanno, Hideyuki, Komuro, Tomoyuki |
| بيانات النشر: |
United States: NASA Center for Aerospace Information (CASI), 2015. |
| سنة النشر: |
2015 |
| مصطلحات موضوعية: |
Fluid Mechanics And Thermodynamics |
| الوصف: |
Radiance measurements in air at enthalpies from 8-20 MJkg have been made over a 250mm diameter flat-faced test article in Japan Aerospace Exploration Agency's HIgh-Enthalpy Shock Tunnel (HIEST). Measurements were made in the ultraviolet region (200-400 nm wavelength) in an attempt to resolve the long-standing discrepancy between theoryand measurements of heat flux over a blunt body; this discrepancy is often attributed toradiation. The spectra obtained indicate the presence of atomic iron vapor in the flowfield.At the highest enthalpies, the radiance is at the blackbody limit. An attempt to model theradiance is made by taking a nominal CFD flowfield without any contamination productsand processing it through a line-by-line radiation simulation tool. Iron vapor is introducedinto the shocked gas ahead of the model and radiation computations are repeated; the molefraction of iron vapor is adjusted to match the data. For the higher enthalpy conditions, theradiance was strongly absorbed and it was necessary to adjust the temperature and NOdensity in the freestream to match the signal below 300 nm. Once the observed spectrawere satisfactorily matched, the radiance to the stagnation point was then computed. It isshown that the impurity radiation is sufficiently large to explain the discrepancy. |
| نوع الوثيقة: |
Report |
| اللغة: |
English |
| URL الوصول: |
https://ntrs.nasa.gov/citations/20190027602 |
| ملاحظات: |
NNA10DE12C |
| رقم الانضمام: |
edsnas.20190027602 |
| قاعدة البيانات: |
NASA Technical Reports |