High Altitude Hypersonic Flowfield Radiation
Abstract
Methods for computing radiation spectra and intensity are compared with available experimental data from three flight tests and five laboratory experiments. These involve both nonequilibrium and equilibrium flow. The comparison was facilitated by development of an improved radiation code, termed NEQAIR 2, incorporating vectorized programming to enable fine-structure spectra to be computed in a practical amount of time. The main sources of computational inaccuracy are found to stem from imperfect understanding of. (1) what temperature or combination thereof in a multi-temperature flowfield governs electronic excitation; (2) the physics of rotational relaxation at very high temperatures; and (3) the reaction rates for NO production at very high temperatures. Computed radiation is most accurate at low altitudes and hypersonic velocities, and least accurate at high altitudes and velocities. Flowfield radiation, Hypersonic, Nonequilibrium, Spectra.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1994
- Accession Number
- ADA281386
Entities
People
- Dean R. Chapman
- Robert W. Maccormack
Organizations
- Stanford University