Numerical Simulation of Flake Orientation During Droplet Impact on Substrates in Spray Painting Processes

A numerical study of flake orientation by droplet impact on dry and wetted solid surfaces for spray painting processes has been carried out. A dynamic contact angle model was applied for the calculation of viscous droplet impact on the dry surface after experimental validation. A user-defined 6-DOF model that concerns to the rigid body motion was implemented in a commercial CFD program to calculate the flake movement inside the droplet. The simulated flake orientations show interesting results that are helpful to understand and to improve painting processes.