Narrow-Band k-Distribution Database for Atomic Radiation in Hypersonic Nonequilibrium Flows

Full-spectrum k-distribution (FSK) and multi-group FSK approaches make it possible to evaluate radiative fluxes at a fraction of the cost needed for line-by-line calculations. However, the required k-distributions need to be assembled from accurate absorption coefficient data for each flow condition, which is computationally expensive. An accurate and compact narrow-band k-distribution database has been developed for the most important species encountered in hypersonic nonequilibrium flow. The database allows users to calculate desired full-spectrum k-distributions through look-up and interpolation. Strategies for k-distribution data generation are outlined. The accuracy of the database is tested by comparing narrow-band mean absorption coefficients and narrow-band emissivities with those obtained from line-by-line calculations. Application of the database to construct full-spectrum k-distributions accurately and efficiently is discussed, and results from a number of heat transfer calculations and cpu-time studies are presented.