Numerical analysis of coupled level set-VOF method on droplet impact on spherical concave surface

In order to explore the mechanism of droplet impact on a spherical concave surface, a numerical model using the coupled level set and volume of fluid method was developed. The mechanism of droplet impact and breakup during spreading was obtained. The impact characteristics were closely related to impact velocity. Droplet impact on a spherical concave surface showed a smaller spread factor, earlier time of central normal jet and larger jet velocity than the impact on a flat surface. The maximum spread factor and relative maximum spread velocity increased exponentially with Reynolds number. The maximum length of jet increased logarithmically with Reynolds number. The maximum jet velocity decreased exponentially with Reynolds number. Through comparison of theoretical analysis models of maximum spread factor, the development direction of analysis model of maximum spreading factor of droplet impact on a concave surface was presented.