Database and Numerical Procedures for Extending the Spectral Range Of Plume Signature Codes

Over many data collection campaigns, a large number of propulsion related signature events have been observed across an extended range of the electromagnetic spectrum. The current suite of plume modeling tools contains the basic framework for flowfield and signature generation, but lacks the underlying physical mechanisms and supporting property databases to properly account for alternate waveband regions. Recent efforts by Spectral Sciences, Inc. (SSI) used innovative computational chemistry techniques and laboratory data to generate a database of chemical rates among ro-vibrational state specific levels to extend the wavelength range of signature codes. The present approach develops and tests innovative procedures to compress the number of database states and rates, making routine applications possible. In Phase I, we will select one propulsion signature event observable, identify the phenomena to account for the complete process from combustion through signature emission, and prioritize the importance of each component as a function of altitude, velocity, and spectral band. We will focus on a single component, upgrade an existing government signature code, and demonstrate the methodology by applying the method to field data. In Phases II/III, we will extend the method to other propulsion signatures, altitudes, and government signature codes. Approved for Public Release | 16-MDA-8917 (15 November 16)