Study of the multi-physics field-coupled model of the two-stage electrostatic precipitator

The two-stage electrostatic precipitator is widely used to purify oil mist particles. However, there is limited research on the influences of relative humidity, particle deposition characteristics, and the generation of gaseous pollutants. Therefore, this paper established a numerical model of the electrostatic oil mist purifier and applied it to a two-stage electrostatic precipitator. Then the model was used to investigate the corona discharge characteristics under different relative humidity conditions in the charged zone, the particle deposition characteristics, the purification efficiency, the ozone concentration distribution, and the oil vapor concentration distribution in the collection zone. The results indicate that, with a constant temperature, the corona current decreases as relative humidity increase, and there is a quadratic relationship between relative humidity and current. The variation in relative humidity has little impact on the purification efficiency. The maximum ozone concentration occurs near the electrode line, and its concentration is influenced by the discharge current and inlet airflow velocity. The oil vapor concentration reaches its maximum value at the side plates, with a value of 19 ppb, while it reaches the minimum value at the collecting zone electrode plate, with a value of 2 ppb. The temperature is the main factor affecting the volatilization of the oil film, with higher temperatures resulting in higher oil vapor.