An optimization approach for fabricating electrospun nanofiber air filters with minimized pressure drop for indoor PM2.5 control

Abstract

Electrospun nanofiber air filters can achieve remarkable particle filtration efficiency with low pressure drop. Therefore, they can potentially be installed in buildings for reducing indoor PM2.5 concentrations. To improve filtration performance, this study developed a design and fabrication approach for electrospun nanofiber air filters with minimized pressure drop under a target PM2.5 filtration efficiency. First, this research developed semi-empirical models for calculating the pressure drop and PM2.5 filtration efficiency of nylon electrospun nanofiber filters using the fabrication parameters of electrospinning time and nylon concentration. With the developed models, this investigation then proposed an optimization approach to minimize the pressure drop under a given PM2.5 filtration efficiency and air velocity. For a given air velocity and PM2.5 filtration efficiency, one can minimize the pressure drop by finding the optimal solution concentration, while the target PM2.5 filtration efficiency can be achieved through adjustment of the electrospinning time. Furthermore, the proposed optimization approach successfully minimized the pressure drop for 110 out of the 125 cases, with an average pressure drop reduction of 32.7%. Finally, this research numerically studied the performance of a window screen coated with the optimized nanofiber filter in reducing indoor PM2.5 of outdoor origin.