Problems of intake air filtration for combustion engines of vehicles

The basic method of protecting the engine against the destructive effects of mineral dust sucked in with the air intake to the engine are air filters. Passenger cars will be equipped with single-stage filters with a filter insert (porous partition) in the form of a panel made of pleated filter paper. Filter papers show insufficient filtration accuracy of dust grains below 5 µm. The principles of shaping traditional filter partitions made of pleated filter paper and the principles of selecting a filter insert for a car engine using the criterion of permissible filtration speed are presented. The principle of operation and construction as well as the properties of filters with axial air flow, which are made in the modern PowerCore technology, are shown, which reduces the filter dimensions, at the same time resulting in lower pressure drop and greater dust absorption, and therefore a longer period of operation. The article pays special attention to the properties of nanofibers, which are produced from polymers using the «electrospinning» technology, and their filtration properties enable the improvement of the efficiency and accuracy of engine intake air filtration. The results of experimental tests of the efficiency and accuracy of filtration and pressure drop performed for several filter beds differing in structure parameters are presented. It has been shown that the nanofiber layer significantly increases the efficiency and accuracy of filtration of dust grains below 5 µm. Low filtration parameters of the filter beds in the initial filtration period have been demonstrated, which negatively affects engine wear.