Pollution emission characteristics of hydrogen-fueled combustor of an aero-engine conversion gas turbine

In order to provide technical support for the low−pollution combustion organization scheme of the hydrogen−fueled combustor,three hydrogen fuel injection modules(lean direct injection(LDI)module and two lean premixed injection(LPIA and LPIB)modules)were designed according to the working conditions and structural parameters of an aero−combustion engine combustor,and their flow field characteristics,fuel−air mixing characteristics and pollution emission characteristics were studied by numerical calculation methods,the NOx emission regression models of the three modules were developed using the particle swarm optimization(PSO)algorithm afterwards. The study shows that the hydrogen injection mode has a large impact on the flow field structure:the central recirculation zone(CRZ)of the LDI module is some distance away from the nozzle,the radial size of the CRZ of the LPIA module is the largest,and the downstream flow field of the LPIB module has the fastest flow velocity;more uniform fuel−air mixing in the combustor assembling the LPIA module compared to the other two modules;under the design condition,the NOx emissions of the LDI module cannot meet the current emission standards of new gas turbines(@15% O2,≤30 mg/m3),while the NOx emissions of the LPI module can meet the standards,and the NOx emissions of the LPIA can reduce 81.6% compared with the LDI module;the NOx emission regression models established for the three modules take into account the effects of combustor inlet pressure,temperature,equivalent ratio and airflow velocity,and their determination coefficients R2 are 0.972, 0.969 and 0.953,respectively. The modules and their performance data and modeling method adopted in this paper can provide effective reference for hydrogen−fueled combustor design. © 2024 Journal of Propulsion Technology. All rights reserved.