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More efficient and durable catalytic converters for the two- and three-wheeler industry in developing countries are required at an affordable cost to reduce vehicle emissions, to maintain them at a low level and therefore to participate in a cleaner and healthier environment. This particularly is true nowadays, because the demand and prices of Platinum Group Metal (PGM) for catalyst are continuously increasing due to i) the worldwide progressive implementation of motorcycles emission legislations similar to Euro 3 Stage requiring catalysts, ii) the need for non-road diesel vehicles to be equipped now with catalyst systems, and iii) the constant increase of the worldwide automobile market. A new generation of metallic substrates with structured foils for catalytic converters is proven to be capable of improving conversion behavior, even with smaller catalyst size.

On one hand, latest worldwide emissions legislation developments aim to reduce NOx and Particulate Matter (PM) emissions of all diesel engines, while on the other hand lower fuel consumption diesel engines are still required for lower fleet average CO₂ emissions. As a consequence of the chosen CO₂ optimized combustion mode, the raw NOx emission increases and as such Selective Catalytic Reduction (SCR) technology will be the future choice for high efficiency NOx aftertreatment. This paper deals with SCR technology and its derivative SCRi® technology, when diesel particle reduction is required, especially for heavy-duty applications. Alongside the developed metal catalyst technologies, a complete SCR reducing agent dosing system is presented. Emission results gained with the SCR or SCRi® technologies on European commercial engines illustrate the potential of these technologies for conversion of NOx and PM emissions.

Diesel engines tend to operate on lower exhaust temperatures, compared to their gasoline counterparts. Exhaust emission control becomes a significant issue at these lower temperatures, as any catalytic converter needs certain light off temperature to commence functioning. The trend so far has been to move the catalytic converters closer to the exhaust manifold, in order to get the benefit of higher temperatures - but most of the applications are limited to the location available after the turbo chargers. This is due the fact that very minute and efficient catalyst is required, if it has to be placed before the turbo charger. This catalyst also needs to be extremely durable to take care of high exotherms which occur within the catalysts and also to prevent any possible damage to the turbo chargers.

Two and Three Wheeler industry in the Asian region is growing at a rapid pace, as commuting by these vehicles is more affordable and efficient, specially in the developing nations. However, tightening of emission legislations, aimed at creating a cleaner and healthier environment, has led to increasingly demanding efforts required in making more efficient engines / vehicles and also focus on effective after-treatment systems. Catalytic converters, being the most preferred option for after-treatment solutions, play an important role in achieving the desired end results. Over the past several years, monolithic catalytic converters with laminar flow profile were being used by automotive industry. These catalytic converters though create some turbulence at the inlet, make the majority of the rest of the flow laminar, thereby reducing the mass transfer of the exhaust gas components to the effective catalytic sites.

Affordable, efficient and durable catalytic converters for the two and three wheeler industry in developing countries like India are required to reduce vehicle emissions and to maintain them at a low level and therefore to participate in a cleaner and healthier environment. A new generation of metallic substrates with structured foils for catalytic converters has been proven capable of improving conversion behavior even with smaller catalyst size. Specially developed foil structures which transform a laminar exhaust gas flow into a turbulent one, which significantly improve exhaust gas mixing behavior in the catalyst. This publication will deal with the analysis of different metallic substrate foil structures for the catalyst conversion performance for the leading “state of the art” four stroke 150 cm3 motorcycle technology developed for the Asian market.

Particulates in Diesel Exhaust Gas have become a major concern of Environment Protection Agencies in the recent years. The main focus was placed on the so called Nano Particles which are the most harmful to human beeings. OEMs for car, light and heavy commercial vehicle industries have been working on different technologies for a number of years to meet the stringent emission legislations. At the same time some countries have started schemes to retrofit older vehicles that are still on the road and greatly contribute to air pollution. The government of Korea took the worldwide lead and defined 3 categories of required PM reduction rates and incentives to LDV and HDV owners who are prepared to retrofit their vehicles.

Emission legislations for the light / medium and heavy duty vehicles are becoming more and more stringent worldwide. Tightening of NOx and Particulate Matter (PM) limits further from Euro III to Euro IV levels has provoked the need of either controlling NOx from the engine measures and use PM control after-treatment devices such as Partial Flow Filters, or, controlling PM from the engine measures and use NOx control devices such as Selective Catalytic Reduction (SCR) systems. Manufacturers have adopted different strategies, depending upon the suitability, cost factors, infrastructure development and ease of maintenance of these systems. PM Metalit®, is a partial flow filter, which captures particulates coming out of the exhaust and re-generates on a continuous basis with the help of Nitrogen Dioxide (NO2) in the exhaust.

Exhaust after-treatment systems will have to become increasingly efficient in order to comply with the strict emission limits that will apply in the European Union and worldwide in future. Moreover, space constraints, weight and low pressure drop are just some of the issues that have to be addressed by an EU III-compliant catalytic system. The development of metallic substrates over the past few years has shown that turbulent-like substrates increase specific catalytic efficiency. This has made it possible to enhance overall performance for a specific catalytic volume or reduce the volume while keeping catalytic efficiency constant. This paper focuses on the emission efficiency of standard, TS and PE metallic substrates. A simulation tool and flow bench measurements were used to develop a test matrix with catalyst similar pressure drop in order to examine different cell densities, substrate lengths and coating technologies.

The new generation of metallic substrates for catalytic converters used in the two and three wheeler industry is capable of improving conversion behavior even with smaller catalyst size. The lowering of production costs due to less use of precious metal is possible. This novel technological application in motorcycle vehicle class improves exhaust emission performance and introduces a new competitive product on the market. Specially developed foil structures, which transform a laminar exhaust gas flow to a turbulent one, significantly improve exhaust gas mixing behavior in the catalyst. This publication is dealing with the analysis of different metallic substrate foil structures for the catalyst conversion performance and the light-off characteristics for the leading state of the art four stroke 150 cm3 motorcycle technology developed for the Asian market.

Over the past several years, monolithic catalytic converters with laminar flow profile are being used by automotive industry. These catalytic converters, though create some turbulence at the inlet, make the majority of the rest of the flow laminar, thereby reducing the mass transfer of the exhaust components to the effective catalytic sites. Improvements were achieved only through the higher cell densities so far. If the design change in the substrates allows the change of exhaust flow from laminar to turbulent, longer residence time can be achieved and more unconverted gases from the core of the channel come closer to the catalyst surfaces facilitating more reaction with the active catalytic sites. The turbulent technology has been successfully developed more recently with metal substrates to get the required turbulent flow characteristics in the substrate channels.

Metallic Catalytic Converters employ alternate layers of flat and corrugated metal foils. To impart higher efficiencies to metallic catalytic converters, there have been progressive developments in the area of foil structures. The constructional details as well as performance behaviour of some of these structures have been reported earlier for automobile applications. In this paper the details of these new structures and the catalyst performance improvement applied to smaller size 2/3 wheeled vehicles are discussed. Transversal Foil Structures (TS) earlier studied and experimented for automobiles have shown improved catalytic performance. Analysis was made for two representative sizes of TS Structure applicable for 2/3 wheelers. It is seen that TS structure improves catalytic converter performance for smaller sizes also. This improvement can be utilized to reduce the Catalytic Converter volume and catalyst loading for same performance as compared to regular substrate.

Catalyst in the exhaust system of Light -duty diesel vehicles operating at low temperatures typical of urban driving does not reach light-off temperature. There are options in metallic substrates for close-couple operations for optimum heat utilization to effect higher temperature for oxicat performance and for efficient operation and regeneration of metallic particulate filter, which by itself is an attractive option for EU IV Norm. The present paper gives an account of developments in this field. Also the paper gives an insight into the developments of new innovative metal foil structures for use in petrol and diesel vehicles, which provides enhanced catalytic efficiencies without increasing cell densities.

Metallic substrates for catalysts constitute a supporting technology to meet the various emission legislations world wide for passenger cars as well as for 2- and 3-wheelers. Hot tubes offer additional advantages, especially for 2- and 3-wheelers in combination with metallic substrates or as independent systems. Low thermal capacity data indicates an early light off. High thermal conductivity assists the catalyst under engine misfiring conditions. The wall thickness of the foil material used is responsible for low back pressure and high engine performance. The greater geometrical surface area of metallic substrates and hot tubes in combination with structured surfaces offers the automotive industry an opportunity to reduce catalyst volume. Simple, economical canning methods are a field of special interest in the automotive industry. These advantages combined allow metallic substrates a significant market share in automotive applications.