The experiment was conducted on a GDI turbocharged
engine fueled with methanol gasoline blends with 0%, 10% and 20% volume
fraction methanol. The effects of blended fuel on particle size distribution,
particle number concentration and mass concentration were studied under lean
burn condition. Experimental results showed that the peak of particle number
concentration gradually increased and the particle size showed a bimodal
distribution with the increase of methanol proportion. Nuclear mode particle
and accumulation mode particle gradually increased and those of M20 blends were
the largest. The peak particle size also increased. The peak size of nuclear
mode particle was 20.5431.62 nm and that of accumulation
mode particle was 56.23100 nm. In addition, the mass
concentration increased with the increase of methanol proportion. The
accumulation mode particle with a size of 316700 nm
obviously increased, the mass concentration of accumulation mode particle
obviously increased with the increase of particle size, and hence the mass
concentration increased. However, the mass concentration of 56.23316 nm particle decreased.