Abstract
Inside automobile engines, it is important to control the generation of liquid film and liquid film behavior. There have been some studies to classify steady wave or transition to breakup and scattering by cross-flow. However, clear visualization measurements of interaction between liquid film and cross-flow are also needed because transition and scattering are indefinite to be predicted. In our experiments, air from wind tunnel flows on the water film in a square duct, and the film is photographed using the high speed camera in various conditions of air and water velocities. It is found that the liquid film behavior can be definitely classified in four, that is smooth, wave, transition and scattering by dimensionless parameters. And the Kelvin-Helmholtz wave transition equation is applicable to transition region the beginning part of our work about the dimensionless numbers.