Effect of Impact Angle and Energy Conservation on the Prompt Splashing of a Single Droplet on a Liquid Pool
摘要
The dynamics of the prompt splashing phenomena and the interplay of different energies (impact, kinetic, and surface energy) when a single droplet impacts a liquid pool were investigated systematically using VOF methodology. The study analyzes the droplet splashing characteristics of perpendicular and oblique impact, mostly morphological evolution such as crown interface, cavity shape, crown height, and pressure field variation under the same Weber Number (We). Four different impact angles viz. θ = 0°, 30°, 45°, and 60° concerning the direction normal to the liquid pool are chosen for the present study. It is observed that the symmetric evolution of the crown interface turns asymmetric with the alteration from perpendicular to an oblique impact, which results in a decrement in the crown height, and ultimately this results in collapses without crown formation at θ = 60°. Instabilities are observed at the neck of the jet under certain fluid conditions due to kinetic energy influencing the surface tension forces. Besides those, the phenomena such as the gas-bubble entrapment, secondary droplet pinching-off from the crown tip, and pressure field variation are also affected by impact angle.