Originally Posted by
tdracer
TThe Dual Annular Combustor design in the GE90 was driven by emissions requirements, and the GEnx uses a very elaborate staged fuel nozzle setup that mimics the low emissions of a DAC without the drawbacks of an actual DAC.
Would DAC mean the dual concentric rings of (for want of a better word) nozzles or flameholders shown in this X-Section? Which seems to create an - interesting - pattern of pressures inside the chamber.
Two sets of small torches instead of single larger ones, which may be where the lower emissions come from?
https://www.researchgate.net/figure/...fig6_269050769