The two-dimensional oil film characteristics of the single-hole injector spray wall impingements in a direct injection gasoline engine were quantitatively analyzed by the laser induced fluorescence method. Results show that the fuel accumulates on the wall in the direction of oil film expansion and forms a thicker oil film on the edge. High injection pressure helps to form an oil film with a lower mass and a thinner thickness

while reducing the jet pulse width can further reduce the fuel adherence rate. Increasing the wall impingement distance can simultaneously reduce the oil film quality and the oil film area

but can not reduce the average thickness of the oil film

so there is no obvious promotion effect on the oil film evaporation. Increasing the spray angle from 15° to 45° can significantly reduce the oil film quality and average thickness.