Total catalytic converter modelling for durability improvement

From the simple drain of flow to the gas cleaning, exhaust systems of automotive vehicles become complex modules playing a decisive role in the control of pollutant emissions and on acoustic comfort. In terms of depollution, the key elements are the catalysts and other systems of gas purification such as particle filters, NOx or SOx traps, etc. Catalyst is a subset in which chemical reactions are initiated with the aim of maintaining the pollutant emissions below certain rates fixed by standards. Evolutions of emission control standards deal with service life of catalytic converters. Mechanical durability should not restrict the lifetime of catalysts. This aspect has led us to develop a prediction tool, with the aim of preselecting design solutions and reducing testing time. To reach such requirements, a total catalytic converter modeling is needed. Many efforts have been made on both numerical modelling and experimental identification. Advanced measurement techniques such as 1D pulsed ESPI have been used. A non-linear damping identification approach based on the wavelet transform of time responses has been developed and validated