Fuel-air mixing in a turbulent coannular pipe flow measured using laser absorption with genetic algorithm-based tomographic reconstruction and modeled with LES

Abstract

This research aims at improving the knowledge base of fuel-air mixing through measurements and modeling. The measurements are from an improved tomographic reconstruction method that is relatively easy to accomplish. A novel aspect of this research is the use of tomography for generating the RMS of fuel concentration. Measurements of fuel concentration for a mixing field were tomographically reconstructed from time resolved line of sight laser absorption measurements. The modeling is done using large eddy simulations (LES). LES predictions were compared to measurements of the mean and RMS of fuel concentration. The LES model predicted time-averaged radial fuel concentration profiles to within 5%, and overpredicted the RMS of fuel concentration slightly, predicting the trends correctly.