Behavior of moving droplet on inclined containment wall: Experiment and model validation

Highlights: • Droplet moving on inclined surface with 56• Droplet velocity model is improved considering the internal flow pattern- effect. • Improved velocity model predicts experimental data better than the previous. • Onset of droplet motion and transition models predict the experimental data well. Understanding the behavior of moving droplet on inclined containment wall is significant to evaluate condensation heat and mass transfer, aerosol wash-down by condensate flow, etc. The models describing moving droplet, such as the onset of motion, the droplet velocity and the flow pattern transition criterion from droplet to rivulet are presented. Concerning the droplet velocity model, the flow field inside droplet and the dynamic contact angle model are considered to evaluate the viscous force and surface tension force respectively acting on fast moving droplet. A new experiment of water droplets moving on inclined surface coated with decontamination paint, DRISE, is performed with the $\mathrm{Re}$ number range 56$\mathrm{Re}$$\mathrm{Re}$ number, the new developed droplet velocity model on the tilted surface and the criterion of the transition from droplet to rivulet are well validated with the data from the DRISE experiment and the experiment from open literature.