Abstract |
The article discusses numerical simulations of the turbulent diffusion equation coupled with electrohydrodynamics (EHD), carried out for plate-plate and wire-plate electrostatic precipitators (ESPs). Local particle concentration profiles and fractional collection efficiencies were evaluated as a function of three dimensionless parameters: the electric Peclet number, the EHD number, and the reduced particle migration velocity. The collection efficiency for the wire-plate ESP is significantly lower than for the plate-plate ESP. For the wire-plate ESP, when the turbulent diffusion coefficient is less than 0.001 sq m/s, collection efficiency is not affected by any turbulence of EHD level. However, when the turbulent diffusion coefficient exceeds this critical value, collection efficiency drops sharply, regardless of the values of the EHD number and particle migration velocity. The critical turbulent diffusion coefficient of the plate-plate ESP is higher (0.005 sq m/s), indicating that collection efficiency is less sensitive to turbulence. The results emphasize the importance of controlling the quality of flow characteristics in the ESP. |