The combustion and emission characteristics of a GDI turbocharged engine fueled with different methanol/gasoline blends respectively were investigated under lean burn conditions. Results show that under lean burn conditions

the equivalent fuel consumption tends to decrease first and then increase with the mixture concentration getting thinner. It will increase with the rise of methanol/gasoline ratio

but lower than the original. In the process of the mixture getting thinner

the peak cylinder pressure and combustion temperature decrease

while the combustion duration and cycle to cycle variability gradually increase

Under lean burn conditions

the CO emissions tend to decrease and the HC emissions decrease first and the increase

while the NOx emissions increase first and then decrease

and will decrease with the increase of the volume fraction of methanol. Moreover

when the engine operates with methanol/gasoline blends

the emission levels of NOx and CO are lower than with gasoline operation.