中文摘要：

采用CFD商用软件STAR-CD对汽油机冷启动过程中燃油蒸发进行三维数值模拟，研究了油滴初直径、油滴初速度、进气温度、燃油温度、喷射定时和转速对燃油蒸发率的影响规律．计算结果表明，进气温度、燃油温度和转速对燃油蒸发有重要影响.进气门开时，在进气温度为-7℃和90℃时，蒸发率分别为5．7％和25．0％；相应地，在燃油温度为0℃和60℃时，燃油蒸发率分别为5．7％和22．0％．油滴初直径和喷射定时对燃油蒸发率有一定影响，油滴初速度对燃油蒸发率影响很小．

英文摘要：

Three-dimensional numerical simulation of fuel evaporation in a gasoline engine during cold start was employed by using the commercial CFD software STAR-CD. This paper mainly presented the effect of multi-parameters on fuel evaporation rate. The parameters were included initial droplet size, initial droplet velocity, intake temperature, fuel temperature, injection timing and engine speed. The simulation results showed that the most influential parameters on the fuel evaporation were： intake temperature, fuel temperature and engine speed. At IVO, with the intake temperature varied from -7℃ to 90℃, the percentage evaporated is 5.7% and 25.0% , respectively. Correspondingly, with the fuel temperature changed from 0℃ to 60℃, the percentage evaporated is 5.7% and 22.0%. The initial droplet size and injection timing also have some effect on the percentage of evaporated fuel. The initial droplet velocity has a relatively-little effect on the fuel evaporation.