Study on the Droplet Jet Impingement Process on Wall Based on DPM-to-VOF Method

Spray atomization is widely used in nuclear power equipment to ensure its safe and stable operation. In the spraying, some droplets will impinge on the equipment wall and expand and evolve in the form of liquid film. This study investigated droplet jet impingement based on Fluent’s Discrete Particle Model-to-Volume of Fluid (DPM-to-VOF, DTV) transition method, and the accuracy of the simulation method was validated using experimental images of two droplet falling processes. The research investigated the influence of droplet injection velocity and incident angle on the wall liquid film morphology and obtained the variation of droplet splash rate with incident conditions. Furthermore, the effects of gravity, surface tension, velocity components, and other factors on the expansion process of liquid film morphology and droplet splash rate during droplet impingement on the wall were analyzed. It is found that increasing the injection velocity could enhance the disturbance to the liquid film, significantly increasing the contact area between the liquid film and the wall and the width and height of the liquid film area. Increasing the incident angle had a significant impact on the change of liquid film morphology, which was reflected in the increase in the width and decrease in the height of the liquid film area, leading to decreased stability of the liquid film surface. The splash rate increased with the increase of injection velocity and incident angle, with the incident angle having a more significant impact on the splash rate.