Collection efficiency of submicrometre particles using single and double DBD in a wire-to-square tube ESP

Abstract

The aim of this work is to study the collection of submicrometre particles charged by a dielectric barrier discharge (DBD) in two types of wire-to-square glass tube electrostatic precipitators (ESPs). They are, respectively, designated as single DBD-ESP and double DBD-ESP, depending on the absence or presence of a dielectric layer around the high-voltage wire electrode. The experiments are performed with incense smoke particles having a mean size of about 0.32 µm. An aerosol spectrometer is employed for characterizing the size distribution of these particles at the outlet of the ESPs. The collection efficiency is estimated for various applied voltages and frequencies (ranges: 8–28 kV, 0.3–1000 Hz) at a fixed air flow rate (5.1 L min−1). The electrical measurements show that in the case of the single DBD-ESP, the discharge mode is rather homogeneous. In contrast, the discharge has a filamentary behaviour in the case of the double DBD-ESP. Results show that the particle collection efficiency of both ESPs is higher at high applied voltages and within a certain frequency range. However, corroborating the collection efficiency results with the power consumption measurements reveals that the double DBD-ESP offers better performances for a larger frequency range.