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Affordable, efficient and durable catalytic converters for the Commercial Vehicle and Non-Road industry in all countries are required to reduce vehicle emissions under real world driving conditions and fulfill future legal requirements. Specially for India traffic conditions and payload to engine size conditions new cost-effective solutions are needed to participate in a cleaner and healthier environment. Metallic substrates with structured foils like the Transversal StructureTM (TS) or the Longitudinal StructureTM (LS) have been proved to be capable of improving conversion behavior, even with smaller catalyst size. Now Vitesco Technologies is developed a new Substrate for Heavy duty applications that specifically maintains the geometric surface area at a very high level and improves further the mass transport of the pollutants, which potentially leads together to very high pollutant conversion rates.

The clear objective of future powertrain development is strongly characterized by lowest emission impact and minimum overall system cost penalty to the customer. In the past decades emission impact has been primarily related to both optimization of combustion process and exhaust after-treatment system efficiency. Nowadays, weight reduction is one of the main objectives for vehicular applications, considering the related improvements both in fuel consumption (i.e. CO2 production) and engine-out emissions. The state of the art of catalytic converter systems for automotive ZEV-oriented applications has yet to be introduces into mass production. This paper investigates the successful application o metallic turbulent structures for catalytic converters along with innovative packaging considerations, such as structured outer mantle, which lead to significant weight reductions, exhaust backpressure minimization and improved overall emission conversion efficiency.

Modern Diesel Engines equipped with Common-Rail Direct Injection and EGR are characterized by an increasingly high combustion efficiency. Consequently the exhaust gas temperature, especially during a cold start, is significantly reduced compared to typical values measured in previous engine generations. This leads to a potential problem with CO emission limit compliance. The present paper deals with an experimental investigation of turbulent-flow metal substrates, carried out on a vehicle roller bench using a production 1.3 Liter diesel engine equipped passenger car. The tested metal supported catalysts proved to yield extremely high conversion rates both during cold start and in warm operation phase. The improved mass transfer efficiency of the advanced metal substrates is related on one hand to the optimized coating technology and, on the other hand, to the enhanced flow performance in the single converter channels which is caused by structured metal foils.

Future emission legislation and new diesel engine technology tighten the requirements for modern diesel vehicle exhaust after-treatment systems. In particular, the oxidation catalyst system requires more efficiency to treat increasing raw emissions of HC and CO at low exhaust gas temperatures resulting from advanced combustion processes. This represents a big challenge for all developers today where the cost of raw materials continues to rise. Splitting the oxidation catalyst volume into two parts and mounting a very small part in front of a turbocharger on Euro III or Euro IV Diesel engines has been proved very efficient: Light off and maximum pollutant conversion rates were improved. New results gained with Pre Turbocharger Catalyst (PTC) on a Euro V type diesel engine are confirming previous observations. The complete after-treatment system of today's vehicles should be designed and developed for the whole life of the vehicle.

Future emission legislation can be met through substantial improvement in the effectiveness of the exhaust gas after-treatment system, the engine and the engine management system. For the catalytic converter, differentiation is necessary between the cold start behavior and the effectiveness at operating temperature. To be catalytically effective, a converter must be heated by the exhaust gas up to its light-off temperature. The major influential parameter for the light-off still is the supply of heat from the exhaust gas. Modification of the cold start calibration of engine control such as spark retard or increased idle speed can increase the temperature level of the exhaust gas. One further possibility is represented by a reduction of the critical mass ahead of the catalyst (exhaust manifold and pipe). Nevertheless the best measure to obtain optimal cold start effectiveness still seems to be locating the converter close to the engine.

Emission legislation for Off Road Engines is forcing the industry to review the engine design, introducing state of the art technology for many components and tailored exhaust gas after treatment architectures. Particulate matter reduction is a crucial issue to be addressed having an influence on overall engine performance and cost. At the present stage there is not a unilateral solution in the industry, as some manufacturers use a combination of very high fuel injection pressure and very efficient DOC, while others rely on the automotive derived DPF technology with active regeneration or SCR-only technology to reach EU Stage IV and US Tier4f. Considering the pros and cons of each solution, VM Motori decided to adopt an innovative solution consisting in a DOC followed by a partial-flow filter PM-Metalit® for the R750 Engine family. The advantages of this solution will be discussed in this paper along with the application work that has been carried over to reach the emission limit.

Modern Diesel Engines equipped with Common-Rail Direct Injection, EGR and optimized combustion technology have been proven to reduce dramatically engine raw emissions both in terms of Nox and Particulate Matter. As a matter of fact the recently introduced FIAT 1.3 JTD 4 Cylinder Engine achieves Euro 4 limits with aid of conventional 2-way oxidation catalyst. Nevertheless some special applications, such as platforms with relatively higher gross vehicle weight possibly yield to PM-related issues. The present paper deals with the development program carried out to design a cost effective aftertreatment solution in order to address particulate matter tailpipe emissions. The major constraint of this development program was the extremely challenging packaging conditions and the absolute demand to avoid any major impact on the system design. The flow-through metal supported PM Filter Catalyst has been extensively tested on the specific vehicle application with aid of roller bench setup.

Future stringent emission levels for NOx and PM will lead to the introduction of innovative combustion processes for diesel engines, such as premixed combustion, with the results to enhance the engine out emission of HC and CO. Therefore very efficient oxidation catalyst will be needed to face this possible issue. This paper deals with the optimization of a EU IV exhaust system by means of innovative metal supported catalyst, as for example the Pre Turbo Catalyst and the Hybrid Catalyst in combination with dedicated catalyst coatings. Moreover a base study over the use of PM-Filter Catalyst has been made, to show the efficiency of such a device with EU IV engine calibration. The second part of the paper deals with the turbulent like structured foils substrates to have an even more efficient diesel oxidation catalyst with very high volumetric efficiency.

Diesel engine emissions regulations throughout the world have changed dramatically over the last 20 years, with the most stringent phase for medium/heavy duty being implemented starting 2007 - 2010. The general perception is, that combination systems including PM reduction devices and NOx aftertreatment, likely SCR will be applied, hence significant additional emissions equipment will need to be added to a diesel engine. The consequences of this will be increased space for packaging and increased cost, to meet the demanding regulations. Traditional substrate technology, while developing extensively for gasoline engines by use of higher cell densities has limitations when applied to CI diesel engines. New developments in substrate and coating technology now enable considerable improvement in the efficiency and packaging space needed to meet certain limit values.

This paper gives a thorough review of the HC/CO emissions challenge and discusses the effects of different diesel oxidation catalyst designs in a pre turbine and post turbine position on steady state and transient turbo charger performance as well as on HC and CO tailpipe emissions, fuel economy and performance of modern Diesel engines. Results from engine dynamometer testing are presented. Both classical diffusive and advanced premixed Diesel combustion modes are investigated to understand the various effects of possible future engine calibration strategies.

The influence of catalyst volume, cell density and precious metal loading on the catalyst efficiency were investigated to design a low cost catalyst system. In a first experiment the specific loading was kept constant for a 500cpsi and a 900cpsi substrate. In a second experiment the palladium loading was reduced on the 900cpsi substrate and the same PM loading was applied to a 1200cpsi substrate with lower volume. Finally the loading was further reduced for the 1200cpsi substrate. The following parameters were studied after aging: Catalyst performance of standard cell density compared to high cell density technology Light-off performance and catalyst efficiency as a function of Palladium loading and substrate cell density Catalyst efficiency as a function of AFR biasing The performance of the aged catalysts was investigated in a lambda sweep test and in light-off tests at an engine bench.

Diesel engine emission regulations throughout the world have progressed over the last 20 years. In the U.S. the most stringent medium/heavy duty standard will be implemented for on highway vehicles starting in 2010. Although changes to engine design will improve engine out emissions, in order to meet both PM and NOx regulations, combination systems including PM and NOx aftertreatment, are planned to be utilized. In order to achieve the required regulations, a new substrate technology has been developed using advanced “turbulent” flow characteristics, and it has been combined with a novel approach to reduce system complexity: the “SCRi™” or “SCR integrated” system. Such a system uses a continuously operating PM-Metalit with advanced “turbulent” SCR-catalysts in a unique configuration. The reduction of both PM and NOx also has to be seen in context with its effect on CO2 emissions.

The study presented in this paper focuses on measures to minimize exhaust gas emissions to meet SULEV targets on a V6 engine by using a cost efficient system configuration. The study consists of three parts. A) In the first stage, the influence of engine management both on raw emissions and catalyst light off performance was optimized. B) Afterwards, the predefined high cell density catalyst system was tested on an engine test bench. In this stage, thermal data and engine out emissions were used for modeling and prediction of light-off performance for further optimized catalyst concepts. C) In the final stage of the program, the emission performance of the test matrix, including high cell density as well as multifunctional single substrate systems, are studied during the FTP cycle. The presented results show the approach to achieve SULEV emission compliance with innovative engine control strategies in combination with a cost effective metallic catalyst design.

Diesel oxidation catalyst and particulate filter technologies are well established and their applications are well known. However, there are certain limitations with both technologies due to their inherent technical characteristics. Both technologies get 75-90% reduction of HC and CO. A typical oxidation catalyst can be applied to almost any heavy duty diesel application and achieve 20 to 30% reduction in PM mass but no significant reduction in the number of PM particles. On the other hand, diesel particulate filters are very effective at removing >90% of the particles by mass and >99% by number. Unfortunately, passive DPF technology cannot be applied to all applications since the filter regeneration is limited by engine out NOx to PM ratio as well as exhaust temperature. For this reason, particulate filters can not universally be applied to older “dirtier” engines with high PM emissions.

Soot filtration represents a major problem for the complete exploiting of Diesel engines characteristics in terms of global efficiency and CO2 emissions. Even though the engines development in the last years let the engine performances improve, exhaust gas after treatment is still required to respect the foreseen limits for soot and NOx emissions. A flow-through particle trap has been presented with a great potential in soot removal without major penalties in terms of exhaust back pressure. The device performance is strictly connected to channel geometry. This paper deals with that relation by means of an experimental-numerical approach.

Recent engine development has been mainly driven by increased specific volumetric power and especially by fuel consumption minimization. On the other hand the stringent emission limits require a very fast cold start that can be reached only using tailored catalyst heating strategy. This kind of thermal management is widely used by engine manufactures although it leads to increased fuel consumption. This fuel penalty is usually higher for high power output engines that have a very low load during emission certification cycle leading to very low exhaust gas temperature and, consequently, the need of additional energy to increase the exhaust gas temperature is high. An alternative way to reach a fast light off minimizing fuel consumption increase is the use of an Electrical Heated Catalyst (EHC) that uses mechanical energy from the engine to generate the electrical energy to heat up the catalyst.

Future stringent emission legislation will require high efficient catalytical systems. Along with engine out emission reduction and advanced wash coat solution the substrate technology will play a key role in order to keep system costs as low as possible. 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 (Transversal Structure) and LS (Longitudinal Structure) metallic substrates. In a first measurement program, standard TS and LS substrates have been compared using a 150cc 4 Stroke engine in dynamic (ECE R40) conditions. In a second test standard and LS substrate have been tested.

Future stringent emission limits both in the European Community and USA require continuously increased conversion efficiency of exhaust after-treatment systems. Besides the obvious targets of fastest light-off performance, overall conversion efficiency and durability, catalytic converters for maximum output engines require highly optimized flow properties as well, in order to create minimum exhaust backpressure for low fuel consumption. This work deals with the design, development and serial introduction of a close coupled main catalyst system using the innovative technology of Perforated Foils (PE). By means of PE-technology, channel-to-channel gas mixing within the metal substrate could be achieved leading to dramatically reduced backpressure values compared with the conventional design.

Nearly all real diesel engines operations are leading to low exhaust temperatures. Standard catalyst technique remains therefore for significant time below light-off. To improve the conversion behavior two approaches were made: placement of tailor-fitted catalysts as close as possible to the engine exhaust port before turbocharger and usage of close coupled catalysts with the so-called hybrid design. Both measures are providing visible progress in reducing diesel engine emissions. Tests were made with modern diesel engines both for passenger cars and heavy-duty vehicles.

1 An experimental study has been carried out on a production vehicle by means of roller-bench emission tests in order to optimize alternative aftertreatment systems. To this aim different comparisons between the production exhaust system and new strategies are discussed in the present paper with aid of both modal emission data and bag tailpipe figures. The present work shows the application of a alternative solution that complies with future emission legislation with regard both to HC, CO, NOx and PM without any major engine power output or fuel consumption penalty.