Abstract:In order to understand the spray characteristics with methanol temperature and spray pressure changes, a high speed camera and 3D laser phase Doppler particle analyzer(PDPA) was used to research the methanol spray as fuel temperature was 25℃, 50℃, 60℃, 70℃ and 80℃ respectively, and methanol injection pressure was 0.3MPa, 0.4MPa, 0.5MPa respectively. The results show that, with the increase of methanol temperature, the spray atomization quality was improved, the liquid core of methanol jet was reduced, and the spray droplet Sauter mean diameter (SMD) was decreased, meanwhile, the location of main jet zone was expanded from 7mm to 10mm. At the same time, spray penetration and the velocity of droplet was first increased and then decreased with the increase of methanol temperature, and when the methanol temperature reached 70℃, they both had the maximum value. When the temperature of methanol remained the same, the increase of injection pressure can improve the velocity of spray droplets, which contributed to the increase of penetration, moreover, the droplet Sauter mean diameter (SMD) decreased obviously. Thus, in the application of methanol fumigated diesel engine, it is an effective measure to improve methanol atomization by increasing methanol temperature and injection pressure to around 70℃ and 0.5MPa, respectively.