Oblique impingement of an ice particle on a water film

In the present study, we experimentally investigated the oblique impinging process of an ice particle on a water film. A parameter study of the impact velocity, impact angle, and water film thickness was carefully carried out. The results showed that three impact categories occurred, namely uprising liquid sheet, crown with a notch, and complete crown. The uprising liquid sheet only occurred in the case when the dimensionless water film thickness was 0.1, which appeared to be independent of the impact velocity and the impact angle. The crown with a notch only occurred in the case when the impact velocity was 23.0 m/s. The left tilt angles of uprising liquid sheet, crown with a notch, and complete crown all increased first and then decreased with the dimensionless time. Among the three experimental parameters investigated in the present study, the dimensionless water film thickness had the most significant effect on the evolutions of the left tilt angles. The dimensionless spreading lengths in x- and y-direction all increased with the increase in dimensionless water film thickness. In addition, the correlations of dimensionless spreading lengths in x- and y-direction were proposed. In addition, the lifetime of complete crown generally increased with the increase in the impact velocity and the dimensionless water film thickness. Within the scope of the present study, the dimensionless maximum height of uprising liquid sheet generally ranged from 3.0 to 3.5. When the impact angle was 30.0°, the dimensionless maximum height of the crown with a notch increased with the increasing dimensionless water film thickness. The present work not only provides a new insight into the study of the ice crystal icing but also offers effective support for the development of efficient anti/de-icing methods.