Simulation Research on Ultra-lean Constant-volume Combustion Initiated by Spark-ignited Micro-fuel-jet
2022-01-0519
03/29/2022
- Event
- Content
- In the ultra-lean combustion mode, the combustion temperature is relatively low, which is expected to avoid the high-temperature NOx generation. And it also can use excess air to fully oxidize CO, HC and Soot, to achieve cleaner combustion. But at the same time, ultra-lean combustion also has difficulties in ignition and flame propagation. This paper used CONVERGE to simulate the combustion process and products of a new ultra-lean combustion mode, which ignited the ultra-lean premixed fuel/air mixture with the spark-ignited micro-fuel-jet, in a constant-volume vessel with a 6-hole GDI injector. The differences of combustion processes and products were simulated for two spark-ignition positions including ‘on’ the micro-jet spray and ‘between’ two micro-jet sprays. It was found that the combustion duration (the time for burned-fuel-ratio from 10% to 90%) if igniting ‘on’ the micro-jet spray could be shortened by about 14.3%, and the amount of NOx generated would increase about 21.0%. At the same time, compared with the homogeneous premixed combustion with traditional spark ignition at the same global fuel/air ratio, the new ultra-lean combustion mode with igniting ‘on’ the micro-jet spray had lower CO, Soot, and NOx emissions, reduced by 49.5%, 72.1%, and 23.3% respectively. The heat release of this new mode was more concentrated with combustion duration shortened by about 20.2%, which would be beneficial to achieve more efficient and cleaner combustion.
- Citation
- Long, Q., Li, M., Zhou, Y., Hu, Z. et al., "Simulation Research on Ultra-lean Constant-volume Combustion Initiated by Spark-ignited Micro-fuel-jet," SAE Technical Paper 2022-01-0519, 2022, .