Visualization of the pre-chamber combustion and main-chamber jets of a narrow throat pre-chamber
2022-01-0566
03/29/2022
- Event
- Content
- Pre-chamber combustion (PCC) has emerged in the last year as a potential solution to mitigate the global warming problem due to its improvement in engine efficiency with low emissions. Research about the combustion process inside the pre-chamber is still representing a challenge in the field. The high pressure and temperatures, the geometrical restrictions, and the quickness of the combustion are factors that limited the detailed study of this process. Some fundamental studies on constant, at low, and medium working pressures have shown the complexity of the process and the influence of high pressures on the turbulence levels. In this study, the combustion process inside a pre-chamber was optically captured under real engine conditions and linked with the jet emergence inside the main-chamber. A novel optical pre-chamber assembly was designed and tested on an optical engine, having combustion only in the pre-chamber volume, with CH4 as fuel. A separate measurement was carried out using a metal pre-chamber assembly to study the emergence of the pre-chamber jet into the main-chamber. The combustion process was studied using a broadband color camera and pressure transducers in both chambers (pre- and main-chamber). Following, the optical pre-chamber assembly was compared to the metal configuration used for engine performance tests. The combustion evolution inside the pre-chamber is progressive, starting from spark plug location, propagating along the cone, and finally covering faster the throat volume. The combustion luminosity exhibited a non-proportional relation with the heat release rate (HRR) due to the CO2* chemiluminescence. The HSV-model (Hue Saturation Value) analysis revealed the predominance of premixed flame combustion during the first stage of the process, followed by infrared flame combustion. Finally, although the optical pre-chamber assembly showed a faster pressure increase, the combustion process is comparable to the metal pre-chamber assembly on a mass-burn scale.
- Citation
- Echeverri Marquez, M., Sharma, P., Hlaing, P., Magnotti, G. et al., "Visualization of the pre-chamber combustion and main-chamber jets of a narrow throat pre-chamber ," SAE Technical Paper 2022-01-0566, 2022, .