Reduced Kinetic Models for the Combustion of Jet Propulsion Fuels

Abstract

Reduced chemical kinetic models to predict the combustion characteristics of jet propulsion fuels are produced and tested. The parent detailed kinetic model has been developed on the basis of a surrogate fuel formulation methodology that utilizes combustion property targets measured for a particular real fuel to formulate a chemical mixture of nalkanes, iso-alkanes and aromatic functionalities to emulate the combustion behavior of specific target jet aviation fuels. Detailed model predictions are compared against reflected shock ignition delays of both pure components and surrogate fuel mixtures. Systematically reduced models for each individual fuel component are produced and used to test the parent model performance against laminar burning velocity. Finally, a range of systematically reduced kinetic models for two, substantially different, validated surrogate fuels for a particular jet aviation fuel are produce and tested to allow the user a choice in computational cost versus reduced model fidelity. A reduced model of 233 species is produced that closely shares the predictability of the detailed model over the tested conditions. Analysis of the models provides a basis for further refinements in describing the chemical kinetic behavior of all conventional and alternative jet fuels. The limitations of the presented approach are discussed and needs for further refinements are identified.