Abstract
Pressures pulsation generated in the exhaust line, by the reciprocating engine, depend of the speed and the load of the engine. Thus, it is difficult, even impossible, to characterize acoustically directly an element of the exhaust line on an engine test bench because of the interactions between the different elements of the exhaust line, and new pulsation constantly being generated at engine outlet.
It is useful to study the pressure pulsation caused by a single blow-down generator [1]. Such a bench has been set up for the study of catalyst converter.
Influences of the area ratio, angle of the cones, permeability of the catalyst, were studied. Main results are exposed below. Influences of those parameters are summarized and final results obtained on an engine are presented.