Chemical Kinetics for Vitiated Flows

The flame stability in typical augmenters is largely determined by vitiated air composition and high preheat temperature of the incoming flow. Presence of significant quantities of CO2 and H2O in the vitiated air will affect the oxidation characteristics of jet fuels by increasing the third-body collision efficiencies of initiation and recombination reactions. Traditionally, kinetic models are validated against data acquired for unvitiated air. Thus, it is essential to validate the kinetic models against data obtained at typical augmenter operating conditions. Combustion Science & Engineering, Inc. proposes to acquire new experimental data using vitiated air at low pressures. The data will include ignition delay time data (at CSE), laminar flame speed data (at Georgia Tech) and flow reactor experiments (at Princeton University). CSE will also develop a model reduction tool to generate reduced models from detailed kinetic mechanisms that are validated against the experimental data acquired in this project. These reduced kinetic models can be implemented in CFD for practical augmenter simulations for commercial applications. In Phase I, experiments will be performed to obtain low pressure ignition delay time and laminar flame speed data. CSE will also evaluate various model reduction strategies to reduce detailed kinetic models for augmenter applications.