A finite-element model for an electrostatic bell sprayer

Abstract Electrostatic rotary atomizers are receiving considerable interest for the application of paint systems, which include primer, basecoat, and clearcoat. Within this paper, a model is described providing some insights into the dynamics and couplings of the physics driving the process. The foundation of the model was built around a Lagrangian particle tracking scheme to simulate the formation of spray patterns for charged droplets. Steady-state spray patterns were computed using an iterative particle source in cell (PSIC) approach, which represents momentum exchange between the droplet and gas phases as a body force. The flow solver is based on a finite-element formulation incorporating the streamlined upwind Petrov Galerkin (SUPG) method for stabilization. Space charge on the surrounding electric field, caused by the motions of charged particles, was computed as a natural extension of the PSIC method.

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