Grant: Automotive Partnership Canada Project

Concern pollutants in vehicle exhaust has led to the development of the catalytic converter, which is a key component of exhaust gas mitigation systems. One of the chief areas of concern is the so-called cold start period, where the catalytic converter is below the light-off temperature, and the conversion of emissions is low. For many automobile journeys, the majority of the emissions are emitted during this period, and thus any method that can reduce the period prior to ignition will give a performance enhancement. One method that has been used to enhance light-off performance is the use of high cell density monolith substrates. However, these monolith supports have a significant price premium compared to a standard monolith and much higher back pressure, which is an important problem. The catalytic converter typically has a larger cross section area (orthogonal to the flow direction) than the exhaust pipe. Furthermore, external heat losses occur because the ambient temperature is lower than the exhaust gas temperature. These factors combine to give a converter core that is hotter than the peripheral area. The main concept to be explored in this work is the Multi-Chamber Catalytic Converter (MCCC). MCCC is a relatively simple modification to the current catalytic converter design in which thin layers of insulating material are introduced into the ceramic honeycomb in a concentric fashion. This layer alters the thermal characteristics of the ceramic honeycomb and disrupts the flow of heat from the inner to the outer parts of the ceramic, which increases the thermal intake of the catalytic converter and reduces the time necessary to reach light-off temperature. Even minor improvements in energy retention could lead to significant reductions in emissions during this critical period. The purpose of this research is thus to conduct a one year research program to yield a rigorous demonstration of a proof-of-concept of the MCCC. The demonstration project must be acceptable to OEM and vehicle manufacturers.