A New Method for Automation and Optimization of the Curve Fit Kinetics Generating Process

Run-time and convergence requirements limit practical Computational Fluid Dynamics (CFD) combustion simulations to simplified chemistry, such as multi-step global kinetic mechanisms. Current methods available for generating reduced global mechanisms are tedious, and the resultant mechanisms often lack accuracy. What is needed, and proposed for development in this SBIR effort, is a software package to efficiently and accurately generate global mechanisms from detailed mechanisms. In Phase I of this SBIR, the feasibility of using optimization algorithms to automate the curve-fit generation process was shown through automating the thermodynamic fits of the current AFRL kinetics code, QuasiGlobalCustomizer. Also, the ability to generate global rates from detailed mechanism calculations based on the Continuously Stirred Tank Reactor (CSTR) model was demonstrated in a preliminary version of the software. In Phase II, the software developed during Phase I will be expanded to allow fitting of the global mechanism to a wide range of combustion phenomena, such as ignition delay, extinction limits, pollutant emissions, flame speed, and others. The final code will have a very intuitive Graphical User Interface (GUI) and will allow the combustion engineer to generate reduced global mechanisms with speed and accuracy.