Experimental study on the synthetic dust loading characteristics of air filters

Abstract

• The loading characteristics of bag-type air filters for ASHRAE and A2 fine test dust were studied through experiments. • A pressure drop empirical equation model was proposed via linear regression. • The dust loading mass is introduced in the evaluation of the air filter pressure drop. The energy consumption of filtration is an important part of the energy consumption of HVAC systems, so reasonable evaluation of the average pressure drop during the entire life cycle of an air filter is very important. However, the loading characteristics of bag-type air filters for ASHRAE test dust and A2 fine test dust have not been well studied. Medium-efficiency bag-type air filters widely used in HVAC systems were selected as the research object, and dust loading experiments at different concentrations of ASHRAE test dust and A2 fine test dust were conducted in order to reveal the evolution of air filter pressure drop under different air flow rate and dust loading state conditions. Based on experimental data and via linear regression, an empirical equation model of pressure drop calculation with air flow rate and dust loading mass as independent variables is proposed, which can be used to predict the pressure drop of air filters. The results show that the absolute value of relative error between the pressure drop values predicted by the empirical equation model and experimental results is basically within 7%, and that the model is accurate and reliable. The applicability of the model is verified through the experimental data from references. Based on this model, it is possible to predict the pressure drop of air filters in HVAC systems under constant or variable air flow rates and different dust loading masses, and to reasonably evaluate the average pressure drop throughout the life cycle of the filter.