Development of a low-pressure loss PM2.5 filter for building natural ventilation

This paper presents the development and experimental testing of an innovative low-pressure loss PM2.5 filter channel that can be integrated in building facades. This indoor-outdoor filter uses electrostatic precipitation (ESP) to reduce outdoor PM2.5 ingress into the indoor environment while ensuring the low airflow resistance that natural ventilation systems require. The filter uses a "U" shaped channel that allows for the integration of ESP and an acoustic attenuation component in a device that fits in the shallow depth of common building facades. The proposed filter device has a 0.5 m height, a 0.4 m width and 0.3 m depth. A 0.1 m opening height allows for a nominal airflow of 70 m3/h with an average inflow velocity of 0.5 m/s. The development and testing work presented in this paper used a combination of laboratory experiments and computational fluid dynamics simulations. Experimental results show that the PM2.5 collection efficiency of the device is more than 60%.