N+3 and N+4 Generation Aeropropulsion Engine Combustors: Part 2 — Medium Size Rich-Dome Engines and Lean-Domes

Comprehensive assessment of the medium size rich-dome engines was conducted leading to the following emissions correlations:Display Formula(1)LTO NOx=1.129×OPR1.0899withR2=0.9248Takeoff NOxEI given byDisplay Formula(2)NOxEI=0.0729×OPR1.7197withR2=0.9603Display FormulaCOEIidle=396.42NOxEITakeoff0.814These correlations may be compared with the following for the CFM56 Tech Insertion:Display FormulaTakeoff NOxEICFM_TI=0.0744×OPR1.7151Display FormulaIdle COEICFM_TI=396.42Takeoff NOxEI0.814Display FormulaIdle HCEICFM_TI=0.1609×Idle COEI-3.1959TALON II takeoff NOxEI data are reproduced well by:Display FormulaNOxEITALON II=0.0167×OPR2.1403TALON II gives 10% lower NOx at 26 OPR and its NOx is comparable with the CFM_TI at 34 OPR.The CFM DAC technology is competitive with LEC’s for the low rated thrust engines. However, interaction between the two domes leads to early quenching with resultant higher idle COEI plateau. On the other hand, the 40 OPR lean DAC gave 25% higher NOx than LEC. Moreover, lean DAC (Gen-1) impacted fuel burn adversely making its likelihood to continue as product discouraging.The second generation lean dome technology initially kicked off under NASA sponsorship with significantly larger funding support from the CFMI and GE Aviation (GEA) led to successful introduction of TAPS into products (GEnx-1B and Gen-2B) with potential applications in other future GEA engines.Copyright © 2013 by ASME