Research on the characteristics and influencing factors of evaporative emission VOCs based on high-pressure fuel system

In the current GB 18352.6-2016 standard, the evaporative pollutant emission test (type IV test) requires that the sum of emission values be lower than the specified threshold (0.70 g/test) for all light vehicles. There are more and more hybrid vehicles equipped with non-integral control of refueling, and it is of great significance to control evaporative emissions by studying the characteristics and influencing factors of VOCs evaporative emissions of these vehicles. The results show that the escape emission of the carbon tank is very low during the whole aging process, which is much lower than the permeation emission of the fuel system, and the proportion of escape emission may increase slightly with the deepening of the aging degree of the carbon tank. The VOCs emitted by osmotic emission are mainly composed of alkanes and aromatic hydrocarbons, and the main components of VOCs emitted by escaping are alkanes, accounting for 70%-98% of the total.