State of the Art E-Coating with High Precision Physics Involved

There are many factors which influences the deposition behavior in the e-coating process. In this paper, the basic theory of the thickness simulation based on the Faraday’s law and the classic model for the distribution of the electric potential governing by the diffusion equation are described. The paint experiment needed to derive the parameters involved in the model is discussed. Moreover, a hydrodynamic model based on Nernst-Planck equation is proposed, which includes three mechanisms of electro-migration, diffusion, and convection. Such a model can cover the influence of paint velocity on the thickness simulation. The Lattice Boltzmann method (LBM) is considered as a numerical solver for the hydrodynamic model. The technique of detection of air bubbles is applied to improve the precision of the thickness simulation.