Study on Fuel Economy and Exhaust Emission of Lean-Burn PFI Engines
Lean-burn engines operate at a very lean air-to-fuel (A/F) ratio under light-load and part-load regions, in order to analyze the effect of engine speed and load on the BSFC (Break Specific Fuel Consumption) and exhaust emission of Lean-burn engine, an experimental research was conducted on a 4 cylinder lean-burn gasoline engine using different A/F ratios. The results show that the CO emission level decrease significantly, HC emission level becomes lower at the same A/F ratio, while the NOx emission increases, hence, advanced technologies are needed to carry out the NOx storage and purge operations in the lean-burn engines. Additionally, the experiment also reveals that the BSFC becomes lower as the engine speed and load increase.
X. B. Yuan et al., "Study on Fuel Economy and Exhaust Emission of Lean-Burn PFI Engines", Applied Mechanics and Materials, Vols. 130-134, pp. 1749-1752, 2012