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Many manufactures are currently working on solutions to fulfill CARB MY 13 requirements for monitoring of diesel particulate filters using a soot sensor. Europe might follow by introducing new OBD limits with EU6 regulation. In this presentation we show results from a study investigating the monitoring capability of a soot sensor in combination with EU6 emission calibration and the OBD matriculate mass limit as proposed in EC 595/2009. A defective diesel particulate filter (DPF) has been detected on roller test bench and under normal driving conditions on public roads. Calibrating a precise soot model is the key factor for the reliability of the particulate filter diagnosis using a soot sensor. Presenter Thomas Czarnecki, Bosch Engineering GmbH

The fatty acid methyl esters (FAME's) - in Europe mostly RME (Rapeseed methyl ester) - are used in several countries as alternative biogene Diesel fuels in various blending ratios with fossil fuels (Bxx). Questions often arise about the influences of these biocomponents on the modern exhaust aftertreatment systems and especially on the regeneration of Diesel particle filters (DPF). In the present work different regeneration procedures of DPF systems were investigated with biofuels B0, B20 & B100. The tested regeneration procedures were: passive regenerations: DOC + CSF; CSF alone, active regenerations: standstill burner; fuel injections & DOC. During each regeneration on-line measurements of regulated and unregulated emission components (nanoparticles & FTIR) were conducted. It can be stated that the increased portion of RME in fuel provokes longer time periods to charge the filter with soot.

Biofuel usage is increasingly expanding thanks to its significant contribution to a well-to-wheel (WTW) reduction of greenhouse gas (GHG) emissions. In addition, stringent emission standards make mandatory the use of Diesel Particulate Filter (DPF) for the particulate emissions control. The different physical properties and chemical composition of biofuels impact the overall engine behaviour. In particular, the PM emissions and the related DPF regeneration strategy are clearly affected by biofuel usage due mainly to its higher oxygen content and lower low heating value (LHV). More specifically, the PM emissions and the related DPF regeneration strategy are clearly affected by biofuel usage due mainly to its higher oxygen content and lower low heating value, respectively. The particle emissions, in fact, are lower mainly because of the higher oxygen content. Subsequently less frequent regenerations are required.

The first commercially available plug-in hybrid electric vehicle (PHEV), the General Motors (GM) Volt, was introduced into the market in mid-December 2010. The Volt uses a series-split powertrain architecture, which provides benefits over the series architecture that typically has been considered for use in electric-range extended vehicles (EREVs). A specialized EREV powertrain, called the Voltec, drives the Volt through its entire range of speed and acceleration with battery power alone and within the limit of battery energy, thereby displacing more fuel with electricity than a PHEV, which characteristically blends electric and engine power together during driving. This paper assesses the benefits and drawbacks of these two different plug-in hybrid electric architectures (series versus series-split) by comparing component sizes, system efficiency, and fuel consumption over urban and highway drive cycles.

The development of PM and NOx reduction system with the combination of DOC included DPF and SCR catalyst in addition to the AOC sub-assembly for NH3 slip protection is described. DPF regeneration strategy and manual regeneration functionality are introduced with using ITH, HCI device on the EUI based EGR, VGT 12.3L diesel engine at the CVS full dilution tunnel test bench. With this system, PM and NOx emission regulation for JPNL was satisfied and DPF regeneration process under steady state condition and transient condition (JE05 mode) were successfully fulfilled. Manual regeneration process was also confirmed and HCI control strategy was validated against the heat loss during transient regeneration mode. Presenter Seung-il Moon

Manganese oxides show high catalytic activity for CO and HC oxidation without including platinum group metals (PGM). However, there are issues with both thermal stability and resistance to sulfur poisoning. We have studied perovskite-type YMnO3 (YMO) with the aim of simultaneously achieving both activity and durability. This paper describes the oxidation activity of PGM-free Ag/i-YMO, which is silver supported on improved-YMO (i-YMO). The Ag/i-YMO was obtained by the following two methods. First, Mn4+ ratio and specific surface area of YMO were increased by optimizing composition and preparation method. Second, the optimum amount of silver was supported on i-YMO. In model gas tests and engine bench tests, the Ag/i-YMO catalyst showed the same level of activity as that of the conventional Pt/?-Al2O3 (Pt = 3.0 g/L). In addition, there was no degradation with respect to either heat treatment (700°C, 90 h, air) or sulfur treatment (600°C to 200°C, total 60 h, 30 ppm SO2).

A conceptual project aimed at understanding the fundamental design considerations concerning the implementation of catalyst systems on outboard marine engines was carried out by Mercury Marine, with the support of the California Air Resources Board. In order to keep a reasonable project scope, only electronic fuel injected four-stroke outboards were considered. While they represent a significant portion of the total number of outboard engines sold in the United States, carbureted four-strokes and direct injected two-strokes pose their own sets of design constraints and were considered to be outside the scope of this study. Recently, three-way catalyst based exhaust emissions aftertreatment systems have been introduced into series production on sterndrive and inboard marine spark ignition engines in North America. The integration of catalyst systems on outboards is much more challenging than on these other marine propulsion alternatives.

This technical paper collection covers the complete particulate filter system. There are papers covering the DOC aging as well as the effect of high sulfur fuel on the DOC. A couple of papers study the effect of ash accumulation and two papers cover a novel new asymmetric cell design and modeling of this new design. Finally we have a paper on gasoline particulate filters.

Papers included in this collection cover the systems engineering experience required to achieve ultra-low emission levels on gasoline light-duty vehicles. Emission system component topics include the development of advanced three-way catalysts, the development of NOX control strategies for gasoline lean burn engines, the application of high cell density substrates to advanced emission systems, and the integration of these components into full vehicle emission systems.

Papers included in this collection cover the systems engineering experience required to achieve ultra-low emission levels on gasoline light-duty vehicles. Emission system component topics include the development of advanced three-way catalysts, the development of NOX control strategies for gasoline lean burn engines, the application of high cell density substrates to advanced emission systems, and the integration of these components into full vehicle emission systems.

Abstract Gasoline particulate filters (GPFs) are important aftertreatment components that enable gasoline direct injection (GDI) engines to meet European Union (EU) 6 and China 6 particulate number emissions regulations for nonvolatile particles greater than 23 nm in diameter. GPFs are rapidly becoming an integral part of the modern GDI aftertreatment system. The Active Exhaust Tuning (EXTUN) Valve is a butterfly valve placed in the tailpipe of an exhaust system that can be electronically positioned to control exhaust noise levels (decibels) under various vehicle operating conditions. This device is positioned downstream of the GPF, and variations in the tuning valve position can impact exhaust backpressures, making it difficult to monitor soot/ash accumulation or detect damage/removal of the GPF substrate. The purpose of this work is to present a unique example of subsystem control and diagnostic architecture for an exhaust system combining GPF and EXTUN.

This technical paper collection includes papers on PM measurement methods, soot generation, alternative methods of PM mass determination, in-cylinder contol of emissions, the effects of EGR, biodiesel fuels, duel fuel systems, soot emissions modeling, PM emissions from gasoline engines, including GDI, ethanol effects, and modeling.

The use of catalyzed diesel particulate filter (CDPF) systems in light duty diesel (LDD) vehicles is becoming increasingly common. The primary functions of the system are to remove carbon monoxide (CO) and hydrocarbons (HC) from the vehicle exhaust stream, while simultaneously reducing the level of particulate matter (PM) emissions to ambient background levels. These systems can comprise either a separate diesel oxidation catalyst (DOC) and a downstream CDPF, or a single unit CDPF with the DOC functions incorporated within the CDPF. The single CDPF unit provides higher regeneration efficiency as it is located nearer to the engine and also cost benefits, as only a single unit is required compared to the alternative separate DOC and CDPF arrangement. A model describing the performance of the single unit CDPF for emissions control has been developed, with particular emphasis on achieving predictions of the CO and HC emissions over transient vehicle drive cycles.

Diesel Particulate Filters (DPF) are widely used to meet 2007 and beyond EPA Particulate Matter (PM) emissions requirements. During the soot loading process, soot is collected inside a porous wall and eventually forms a soot cake layer on the surface of the DPF inlet channel walls. A densely packaged soot layer and reduced pore size due to Particulate Matter (PM) deposition will reduce overall DPF wall permeability which results in increasing pressure drop across the DPF substrate. A regeneration process needs to be enacted to burn out all the soot collected inside the DPF. Soot mass is not always evenly distributed as the distribution is affected by the flow and temperature distribution at the DPF inlet. As a result, the heat release which is determined by the burn rate is locally dependent. High temperature gradients are often found inside DPF substrate as a result of these locally dependent burn rates.

The upcoming Euro VI emission legislation for Heavy Duty Diesel engines can be complied with by using a combination of a wall flow DPF and a UREA SCR-system. This paper describes investigations of NOx and PM reduction by a combination of SCR-catalyst and an (uncoated) Diesel particulate filter (DPF), performed on a fully transient heavy-duty test bench. Soot loading and passive regeneration of the DPF for different configurations of both components and active regeneration by fuel injection into the exhaust gas line were investigated. The impact of DPF on SCR-catalyst as well as SCR-catalyst impact on DPF was analyzed in terms of NOx-conversion and regeneration efficiency of the filter under steady-state and transient operating conditions. The NOx-conversions for the configuration SCR-catalyst in front of DPF were higher for all operating conditions than for the combination DPF in front of SCR-catalyst.

Selective Catalytic Reduction (SCR) catalysts have been demonstrated as effective for controlling NOx emissions from diesel engines, maintaining high NOx conversion even after the extended high temperature exposure encountered in systems with active filter regenerations. As future diesel emission regulations are expected to be further reduced, packaging a large volume of SCR catalysts in diesel exhaust systems, along with DOC and particulate filter catalysts, will be challenging. One method to reduce the total volume of catalysts in diesel exhaust systems is to combine the SCR and DPF catalysts by coating SCR catalyst technology on particulate filters. In this work, engine evaluation of SCR coated filters has been conducted to determine the viability of the technology. Steady-state engine evaluations demonstrated that high NOx conversions can be achieved for SCR coated filters after high temperature oven aging.

Selective Catalytic Reduction (SCR) catalysts have been designed to reduce NOx with the assistance of an ammonia-based reductant. Diesel Particulate Filters (DPF) have been designed to trap and eventually oxidize particulate matter (PM). Combining the SCR function within the wall of a high porosity particulate filter substrate has the potential to reduce the overall complexity of the aftertreatment system while maintaining the required NOx and PM performance. The concept, termed Selective Catalytic Reduction Filter (SCRF) was studied using a synthetic gas bench to determine the NOx conversion robustness from soot, coke, and hydrocarbon deposition. Soot deposition, coke derived from propylene exposure, and coke derived from diesel fuel exposure negatively affected the NOx conversion. The type of soot and/or coke responsible for the inhibited NOx conversion did not contribute to the SCRF backpressure.

Ethanol has been gaining attention as a partial substitute in North American pump gasoline in amounts up to 85% ethanol and 15% gasoline, or what is commonly known as “E85”. The problems with E85 fuel for cold start emissions relative to gasoline fuel are the lower energy density and vapor pressure for combustion. Each contributes to excess E85 fuel injected during cold start for comparable combustion quality and drivability to gasoline. The excess emissions occur before the first three-way catalyst (TWC) converter is warmed-up and active for engine-out exhaust conversion. The treatment of non-methane organic gas (NMOG) emissions from the combustion of E85 and gasoline was evaluated using several different zeolite based hydrocarbon (HC) traps coated with different precious metal loadings and ratios. These catalyzed HC traps were evaluated in a flow reactor and also on a gasoline Partial Zero Emissions Vehicle (PZEV) with experimental flexible fuel capability.

An advanced exhaust aftertreatment system is characterized following end-of-life catalyst aging to meet final Tier 4 off-highway emission requirements. This system consists of a fuel dosing system, mixing elements, fuel reformer, lean NOx trap (LNT), diesel particulate filter (DPF), and a selective catalytic reduction (SCR) catalyst. The fuel reformer is used to generate hydrogen (H2) and carbon monoxide (CO) from injected diesel fuel. These reductants are used to regenerate and desulfate the LNT catalyst. NOx emissions are reduced using the combination of the LNT and SCR catalysts. During LNT regeneration, ammonia (NH3) is intentionally released from the LNT and stored on the downstream SCR catalyst to further reduce NOx that passed through the LNT catalyst. This paper addresses system durability as the catalysts were aged to 500 desulfation events using an off-highway diesel engine.

A diesel particulate filter (DPF) controls and maintains a constant pressure drop across the filter by repeating the regeneration process for PM (Particulate Matter). However, the regeneration results in ash accumulation on the DPF. Although this ash accumulation is very slow, it eventually causes increased pressure drop which affects the product life of the DPF. Metal elements in the lubricant additives in the engine oil are the source of the ash. Since ash is an oxidized substance, the amount of ash produced depends on such factors as the amount of oil consumed in the engine and the kinds of lubricant additives contained in engine oil. According to the reference literature [1-3], ash accumulates on a DPF differently depending on use of either a passive regeneration system or an active regeneration system. With the passive regeneration system, ash accumulates uniformly on the filter wall while ash accumulates near the outlet of the filter with the active regeneration system.