Experimental Characterization of Fuel-Air Mixing in a Multi-Hole Tube

This paper reports our recent research work on the mixing of fuel and air in a multi-hole tube. The multi-hole tube is an important component used for Lean Premixed Prevaporized (LPP), low emission combustion in a micro gas turbine. A baseline configuration of the multi-hole tube is investigated herein. Mixing characterization experiments are conducted by mapping the distribution of fuel-air ratios at the tube exit with a gas analyzer. Experimental results indicate that the matching of fuel atomization and flow field is the primary factor affecting fuel-air mixture uniformity. Based on the experimental results of the baseline configuration, a systematic and parametric configuration optimization can be then attempted. Experimental results with a modified configuration demonstrate improved mixing uniformity at the tube exit as compared to the baseline configuration, thereby signifying the importance of developing multi-hole tube design rules.