Multi-scale simulation of the gas flow through electrostatic precipitators

The gas flow distribution significantly affects the collecting performance of an Electrostatic Precipitators (ESP) system. Computational Fluid Dynamics (CFD) method is here used to study the gas flow through the ESP system at different scales and in a coupled fashion. Firstly, numerical experiments are conducted at an orifice scale (unit cell study) and ESP unit scale (collection unit study) respectively, to determine the parameters of the perforated plates and ESP unit, such as the pressure drop coefficients. Flow distribution in the large scale ESP system is then simulated and adjusted based on a simplified network model. The simulation results and experiment data match well not only qualitatively but also quantitatively. The study shows that the multi-scale CFD approach is suited to predict the gas flow in ESP systems and the results provide useful guidance for ESP design and control.