Development of a Jet A Chemical Surrogate Model Using High Pressure Shock Tube Speciation Data

A proposed solution to the challenge of coupling CFD codes with chemical kinetic models for jet fuels is to develop a reasonable model of the actual fuel through the use of a surrogate fuel, a representative of the real fuel. In the present work a detailed chemical kinetic model for the n-dodecane/iso-octane/n-propylbenzene/1,3,5-trimethylbenzene “2nd Generation” surrogate has been developed and validated against experimental data conducted for this study and from literature. The experimental work was conducted in the High Pressure Single Pulse Shock Tube at the University of Illinois at Chicago. The experiments on the paraffin components, surrogate fuels and the real fuel were conducted at two nominal pressures of 25 and 50 atm, at equivalence ratios from 0.46 to 2.05 and ∞, and at temperatures between 835 and 1757 K. The stable intermediates species were quantified using a GC and a GC/MS apparatus connected directly to the endwall of the shock tube. A comparison between the measured intermediate species and oxygen from the real fuel and the proposed 2nd Generation Surrogate developed by the co-investigators at the group at Princeton University determined the validity of the methodology for the formulation of surrogate fuels. Experimentally, the oxidation of the single component fuels showed that the fuels decay through pyrolytic decomposition at conditions studied; therefore, indicating the importance of studying fuel pyrolysis and the development of models using pyrolytic experimental data. Experimental data from single component fuels were used to validate and revise a recently published surrogate model. This revised surrogate model led to the development of the 2nd Generation Surrogate model using the aromatic models developed by another researcher at HPST laboratory. The developed 2nd Generation Surrogate model showed excellent simulation of fuel and oxygen decay and the formation/consumption of the major and minor species when compared to experimental data. The present study makes available a detailed high temperature chemical kinetic model for the 2nd Generation Surrogate and an experimental speciation database for the paraffin surrogate fuel components, surrogate fuels, and Jet A POSF 4658.