Pilot Injector Redesign to Reduce N+3 Cycle Emissions for a Gas-Turbine Combustor

Ajmani, Kumud ; Lee, Phil ; Chang, Clarence ; Tacina, Kathleen M

关键词: AERODYNAMIC STABILITY;    COMBUSTION CHAMBERS;    COMPUTATIONAL FLUID DYNAMICS;    DESIGN ANALYSIS;    GRID GENERATION (MATHEMATICS);    INJECTORS;    REACTING FLOW;    SPRAY CHARACTERISTICS;    TWO PHASE FLOW;    NITROGEN OXIDES;   

RP-ID  :  GRC-E-DAA-TN70810

学科分类：航空航天科学

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

An overview is given of an effort for the use of CFD analysis to complement design and configuration definition of third generation Lean-Direct Injection combustion concepts (LDI-3) for NASA’s N+3 program. The National Combustion Code (OpenNCC) was used to perform non-reacting and two-phase reacting flow computations for a three-cup, nineteen-element flame tube array with redesigned pilot injectors to improve spray and emissions characteristics when compared to a previous LDI-3 design. All computations were performed with a consistent approach to mesh-generation, spray modeling, ignition and kinetics modeling for a ‘medium-power’ cycle condition. Computational predictions of the aerodynamics of a new pre-filming pilot injector were used to arrive at an optimized aerothermal design that meets effective area and fuel-air mixing criteria. The newly designed pilot injectors were shown to provide considerable improvements in aerodynamic stability, flame-tube pattern factor and NOx emissions, when compared to the original design.