Droplet Impact and Coalescence

In CACT we have developed 3D numerical models, using a Volume-of-Fluid (VOF) method, to simulate droplet impact and coalescence on a surface. The model is used to simulate the formation of coatings by droplets sprayed on a substrate. Predictions from the model have been validated by comparing them with photographs of overlapping droplets landing on a surface. The model is also useful for studying the entrapment of air bubbles under droplets, which is important in understanding how these bubbles are formed in spray coatings.