Electrospun nylon-66 nanofiber coated filter media for engine air filtration applications

Air filtration plays a vital role in the performance and operations of engines, especially for heavy-duty combat vehicles operating in the desert environment. Conventional cellulose media comprises micro-fibers exhibiting low filtration efficiency for particles within the range of 0.1 to 0.5 mu m (most penetrating particle size, MPPS). Nanofiber coating on cellulose media can increase the filtration efficiency, however, with the penalty of an increase in pressure drop. The features of nylon-66 nanofibers, such as high mechanical strength, greater thermal stability, and high surface-to-volume ratio, will be beneficial for developing nano-coated filter media. In this study, electrospun nylon-66 nanofibers were coated over two cellulose-based filter media and tested on an air filtration test rig that employs a suction-type blower replicating the realistic condition of a heavy-duty engine intake. The test rig was fabricated to evaluate the performance of the nano-coated filter media in terms of pressure drop, filtration efficiency, and quality factor (Q-factor). The experimental results demonstrated that the nylon-66 nano-coated media have higher Q-factor (in the MPPS range) than the cellulose media due to the increased filtration efficiency compared to the rise in pressure drop. Therefore, such electrospun nylon-66 nanofiber-coated air filters can be an alternative to conventional cellulose media.