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Simmons, F. S.

Publications and source records attributed to Simmons, F. S..

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

A band model formulation for very nonuniform paths.

Anomalous behavior has been observed when molecular band-models incorporating the Curtis-Godson or similar approximations are applied to problems characterized by a large variation in temperature along the optical path. The nature of this misbehavior has been examined and a procedure has been developed for its suppression by the introduction of a less restrictive assumption in the derivation of the band model from the basic equation of transfer.

Lindquist, G. H.↗
NASA NTRS1972

Measurement of temperature profiles in flames by emission-absorption spectroscopy

An investigation was conducted to explore the use of infrared and ultraviolet emission-absorption spectroscopy for determination of temperature profiles in flames. Spectral radiances and absorptances were measured in the 2.7-micron H2O band and the 3064-A OH band in H2/O2 flames for several temperature profiles which were directly measured by a sodium line-reversal technique. The temperature profiles, determined by inversion of the infrared and ultraviolet spectra, showed an average disagreement with line-reversal measurements of 50 K for the infrared and 200 K for the ultraviolet at a temperature of 2600 K. The reasons for these discrepancies are discussed in some detail.

Simmons, F. S.↗