Abstract
In this research, the maximum deformation ratio of water-based paint droplets impacting and spreading onto a flat solid surface was investigated numerically based on the Navier–Stokes equation coupled with the level set method. The effects of droplet size, impact velocity, and equilibrium contact angle are taken into account. The maximum deformation ratio increases as droplet size and impact velocity increase, and can scale as We1/4, where We is the Weber number, for the case of the effect of the droplet size. Finally, the effect of equilibrium contact angle is investigated, and the result shows that spreading radius decreases with the increase in equilibrium contact angle, whereas the height increases. When the dimensionless time t* < 0.3, there is a linear relationship between the dimensionless spreading radius and the dimensionless time to the 1/2 power. For the case of 80° ≤ θe ≤ 120°, where θe is the equilibrium contact angle, the simulation result of the maximum deformation ratio follows the fitting result. The research on the maximum deformation ratio of water-based paint is useful for water-based paint applications in the automobile industry, as well as in the biomedical industry and the real estate industry. Please check all the part in the whole passage that highlighted in blue whether retains meaning before.
Highlights
The widespread application of the impact and spread of liquid droplets in such areas as agriculture, thermal spray, lab-on-a-chip, and coating [1,2,3], continues to receive attention
Due to the important fluid mechanics in these processes, both experiments and numerical simulations have been implemented in recent years to research droplets’ dynamic behaviors after impact, which has been helpful in understanding droplet interactions with liquid and solid surfaces
Amirfazli et al [6,7,8] conducted series experiments to study the dynamic behaviors of liquid droplets under different effects, e.g., the droplet size dependence on contact angles, the electric fields on contact angles, the surface tension of droplets for different materials, and the receding contact angles of droplets and the rebound time
Summary
The widespread application of the impact and spread of liquid droplets in such areas as agriculture, thermal spray, lab-on-a-chip, and coating [1,2,3], continues to receive attention. Due to the important fluid mechanics in these processes, both experiments and numerical simulations have been implemented in recent years to research droplets’ dynamic behaviors after impact, which has been helpful in understanding droplet interactions with liquid and solid surfaces. Roisman et al [5] experimentally and theoretically studied the impact of a single droplet onto a dry surface by implementing the inertial effect, surface tension, viscous, and wettability. Amirfazli et al [6,7,8] conducted series experiments to study the dynamic behaviors of liquid droplets under different effects, e.g., the droplet size dependence on contact angles, the electric fields on contact angles, the surface tension of droplets for different materials, and the receding contact angles of droplets and the rebound time. Clanet et al [11] studied the impact of liquid droplets of low viscosity on Coatings 2017, 7, 81; doi:10.3390/coatings7060081 www.mdpi.com/journal/coatings
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
