Factors Affecting the Performance of Engine Air Filters

Abrasive particles entering an engine because of inadequate air filtration can cause excessive wear, which may lead to premature engine failure. Despite the importance of filtration in engine systems, there is little understanding of the dynamics of the filtration process. Often, limited space is available for an engine air induction system. Therefore, filters are designed in smaller packages, resulting in higher aerosol velocities through the primary filter material. High aerosol velocities may cause dust re-entrainment and increase the amount of dust penetrating the filter. Our experiments with cellulose and synthetic-type filter media show examples of dust reentrainment for fine and coarse dust. Conditions for dust particle re-entrainment are discussed.