(Research carried out by a student,SARSAH EMMANUEL AKONO)
Similar trends in engine performance were obtained for the air filters tested. However, results show that while some air filters (foam filters of longer length with smaller pore sizes) have little effect on engine performance, others (paper filters of shorter length and smaller pore sizes) strongly affected engine performance. It was also found that dust particles accumulated near the downstream side of the air filters. High concentration of particles located at the downstream part is explained by the fact that, besides the particles collected in this area, the dust washed from the upstream part of the filter also passes through the downstream part. This shows that filters get clogged first downstream and gradually moves upstream of the filter.
It has also been seen that when the Harmattan season set in, the pressure drop across filters will increase significantly and cause clogging of the filters within a short period. Air filters in vehicles that ply an untarred roads exhibit higher pressure drops than those used in vehicles on tarred roads.”
At the end of his investigation It was found that different filters because of structure and shape affect engine performance and effectiveness.