In the scope of this study, an existing multi-physics solver to simulate particle, flow and electrostatic interactions for powder coating applications has been extended to incorporate moving coating pistols. Although the existing solver has been validated experimentally, the lack of the capability to incorporate the motion of a coating pistol prevented it from directly simulating real-life industrial applications.

Powder coating is an environmentally friendly alternative to conventional liquid paint-based surface finishing methods, especially suited for thin coatings. It is employed in a vast range of industrial applications (automotive, household appliances, etc.). The process involves a powder cloud transported along with airflow within a coating pistol, where an electrical corona is formed at the tip of a mounted electrode.

After passing through the corona, the solid particles are ionized and following their discharge from the pistol, they coat a grounded substrate upon impact. Due to the complex interaction involved among the fluid dynamic, electrostatic forces and the motion of individual powder particles, the process is extremely challenging to simulate. Therefore, in the lack of scientific tools, the industry has relied mainly on trial-and-error-based methods and practical know-how.

To remedy this situation, a multiphysics solver capable of taking into the aforementioned interactions has been developed within the framework of OpenFOAM.