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A 500 hours endurance test was performed with a heavy-duty engine (Euro IV); MAN type D 0836 LFL 51 equipped with a PM-Kat®. As fuel 100% biodiesel was used that met the European specification EN 14214. The 500 hours endurance test included both the European stationary and transient cycle (ESC and ETC) as well as longer stationary phases. During the test, regulated emissions (carbon monoxide, nitrogen oxides, hydrocarbons and particulate matter), the particle number distribution and the aldehydes emission were continuously measured. For comparison, tests with fossil diesel fuel were performed before and after the endurance test. During the endurance test, the engine was failure-free for 500 hours with the biogenic fuel. There were almost no differences in specific fuel consumption during the test, but the average exhaust gas temperature increased by about 15°C over the time. Emissions changed only slightly during the test.

TERBAN® hydrogenated nitrile rubber (HNBR) is a specialty elastomer used in demanding engineering applications such as the automotive, heavy duty, and industrial markets. It has excellent combination of heat, oil and abrasion resistance in addition to its high mechanical strength, very good dynamic and sealing properties. This paper will present data on aging HNBR for five thousand hours in an aggressive and un-stabilized B30A biodiesel fuel blend (70% ULSD, 30% SME, and an aggressive additive package) and explore the effect of HNBR polymer properties and vulcanizate composition on the performance in such fuel blends.

A 3.4 kW, 42 V permanent magnet alternator based high power generation system was built and tested in the Delphi R&D laboratory. It is belt driven system with 3.37: 1 pulley ratio. The size of the alternator is slightly less than the production CS-144 Lundell machine with 1/3 less inertia. For cost reasons, the controller uses a single SCR bridge rectifier. The prototype, which is capable of producing 34A/80A at idle/cruising speed, has been tested in the laboratory yielding 84.5%/70.7% efficiencies. Up to cruising speed, the system shows an improvement in full load efficiencies of 5-6 percentile points over a similar 14 V permanent magnet machine with dual SCR bridge. This efficiency improvement is due to the reduction in the converter losses as the current is reduced to one third of its 14 V values even with the same copper losses in both machines.

In July 1997, the Pacific Northwest and Alaska Regional Bioenergy Program, in cooperation with several industrial and institutional partners initiated a long-haul 322,000 km (200,000 mile) operational demonstration using a biodiesel and diesel fuel blend in a 324 kW (435 HP), Caterpillar 3406E Engine, and a Kenworth Class 8 heavy duty truck. This project was designed to: develop definitive biodiesel performance information, collect emissions data for both regulated and non-regulated compounds including mutagenic activity, and collect heavy-duty operational engine performance and durability information. To assess long-term engine durability and wear; including injector, valve and port deposit formations; the engine was dismantled for inspection and evaluation at the conclusion of the demonstration. The fuel used was a 50% blend of biodiesel produced from used cooking oil (hydrogenated soy ethyl ester) and 50% 2-D petroleum diesel.

A 3D-CFD model with detailed chemical kinetics was developed to investigate the combustion characteristics of HCCI engines, especially those fueled with hydrogen and n-heptane. The effects of changes in some of the key important variables that included compression ratio and chamber surface temperature on the combustion processes were investigated. Particular attention was given, while using a finer 3-D mesh, to the development of combustion within the chamber crevices between the piston top-land and cylinder wall. It is shown that changes in the combustion chamber wall surface temperature values influence greatly the autoignition timing and location of its first occurrence within the chamber. With high chamber wall temperatures, autoignition takes place first at regions near the cylinder wall while with low surface temperatures; autoignition takes place closer to the central region of the mixture charge.

A 14 litre turbo charged intercooled diesel engine has been re-engineered to operate as a spark ignition engine fuelled with natural gas. The design targets were for an efficient engine with low emissions using the lean burn capability of natural gas but without sacrificing power output. The resulting ultra lean burn spark ignition engine achieves diesel engine thermal efficiency, with a much reduced NOx emissions though higher NMHC emissions. The engine changes included revised compression ratio, and combustion chamber shape, inlet system modifications to increase turbulence during combustion, i.e., a “smart burn” system, and a new engine management strategy using a “drive by wire” computer control of fuel and throttle and spark timing. The engine has begun duty in an articulated truck in a short haul parts delivery operation, and monitoring of the in service performance has begun.

The low auto-ignition temperature, rapid evaporation and high cetane number of dimethyl ether (DME) enables the use of low-pressure direct injection in compression ignition engines, thus potentially bringing the cost of the injection system down. This in turn holds the promise of bringing CI efficiency to even the smallest engines. A 50cc crankcase scavenged two-stroke CI engine was built based on moped parts. The major alterations were a new cylinder head and a 100 bar DI system using a GDI-type injector. Power is limited by carbon monoxide emission but smoke-free operation and NOx < 200ppm is achieved at all points of operation.

The SAE Mini Baja® competition is an extremely popular design competition that focuses on the design of an off-road vehicle for performance and cost-of-production. A 2006-07 EPA P3 Phase I grant was awarded to the University of Alabama at Birmingham to convert a vehicle created for the SAE Mini Baja® competition to a biodiesel vehicle. Because of the major size difference in the diesel engine chosen compared to the much smaller gasoline engine, conversion of the Baja vehicle required considerably more effort than expected. While many mechanical aspects of the bio-diesel conversion were more complicated than expected, the students were successful in creating bio-diesel and in modifying important vehicle systems. The students also gained a substantial understanding of the economical and environmental aspects of alternative fuel generation. Through the conversion experience gained at UAB, the rules for a new competition were explored.

Reliable motor vehicle emission predictions are needed to ensure sound policy decisions. This study reports on a comparison between measured in-tunnel fleet emissions and predictions made with two new Australian vehicle emission software programs (COPERT Australia and PΔP) for one air pollutant: nitrogen oxides (NOx). Measurements were taken from a 6.8 km tolled motorway tunnel that links several major roads in Brisbane, Australia. The validation study suggests that modelled vehicle emissions of NOx are similar to those measured in the tunnel with a prediction error less than ±25% for both light-duty and heavy-duty vehicles. A possible reason for the difference is a suspected younger and cleaner fleet in the tunnel as compared with the Queensland average fleet. Further analysis of license plate information is anticipated to verify this.

Performance of a CNG (Compressed natural gas) two stroke cycle S.I. engine using intermittent low pressure fuel injection from scavenging ports is investigated experimentally. The test engine is a two cylinder, 398 cm3, two stroke cycle spark ignition engine. Gaseous fuel injectors are attached at the engine block, and a CNG is injected into the scavenging passage through a fuel injection pipe. The fuel injection pressure is set at 0.255 MPa, and the fuel is injected intermittently during the scavenging process. The length and tip geometry of the fuel injection pipe are varied, and the effect on the engine performance is investigated. Using the scavenging port fuel injection, the BSFC is reduced by 25 %, and the lean burn limit extends from λ = 1.2 to 1.46, at the maximum. The peak of the NOx emission shifts to leaner side, and the THC emission is reduced by 47 % at the maximum.

A hydrogen economy is an increasingly popular solution to lower global carbon dioxide emissions. Previous research has been focused on the economic conditions necessary for hydrogen to be cost competitive, which tends to neglect the effectiveness of greenhouse gas mitigation for the very solutions proposed. The holistic carbon footprint assessment of hydrogen production, distribution, and utilization methods, otherwise known as “well-to-wheels” carbon intensity, is critical to ensure the new hydrogen strategies proposed are effective in reducing global carbon emissions. When looking at these total carbon intensities, however, there is no single clear consensus regarding the pathway forward. When comparing the two fundamental technologies of steam methane reforming and electrolysis, there are different scenarios where either technology has a “greener” outcome.

Life Cycle Analysis (LCA) considers the key environmental impacts for the entire life cycle of alternative products or processes in order to select the best alternative. An ideal LCA would be an expensive and time consuming process because any product or process typically involves many interacting systems and a considerable amount of data must be analysed for each system. Practical LCA methods approximate the results of an ideal analysis by setting limited analysis boundaries and by accepting some uncertainty in the data values for the systems considered. However, there is no consensus in the LCA field on the correct method of selecting boundaries or on the treatment of data set uncertainty. This paper demonstrates a new method of selecting system boundaries for LCA studies and presents a brief discussion on applying Monte Carlo Analysis to treat the uncertainty questions in LCA.

To meet increasingly stringent diesel engine emission regulations, diesel engines are required to use ultra-low sulfur diesel (ULSD) and are equipped with advanced aftertreatment systems. Cu-SSZ-13 zeolite catalysts are widely used as selective catalytic reduction (SCR) catalysts due to their high NOx reduction and excellent hydrothermal stability. However, active Cu sites of Cu-SSZ-13 catalysts can be poisoned by exposure to engine exhaust sulfur species. This poison effect can be mitigated with the use of ULSD and high temperature exposure from engine operation. On the other hand, ULSD is still not universally available where regulations require it, and vehicles may inadvertently operate with high sulfur diesel fuel (HSD) in some locations. The high concentration of exhaust sulfur species resulting from HSD combustion may rapidly poison the Cu-SSZ-13 SCR catalyst. In this study, the catalytic performance of a sulfur poisoned Cu-SSZ-13 SCR catalyst is analyzed.

An advanced catalytic exhaust after-treatment system addresses the problem of NOX emissions from heavy-duty diesel trucks, relying on real-time catalyst modelling. The system consists of de-NOX catalysts, a device for injection of a reducing agent (diesel fuel) upstream the catalysts, and computer programmes to control the injection of the reducing agent and to model the engine and catalysts in real time. Experiments with 5 different air-assisted injectors were performed to determine the effect of injector design on the distribution of the injected diesel in the exhaust gas stream. A two-injector set-up was investigated to determine whether system efficiency could be increased without increasing the amount of catalyst or the amount of reducing agent necessary for the desired outcome. The results were verified by performing European standard transient cycle tests as well as stationary tests.

While the request of diesel engine is recently increased due to its excellent fuel economy benefit, the regulation of emission becomes reinforced. The variety of method such as engine technologies and aftertreatment systems have been developed and applied to meet the criteria of regulation so far. One of recognizable technologies utilized in a heavy commercial vehicle is SCR system using urea solution as a reductant, which eliminates NOx. This paper includes the experiment of a diesel engine equipped with Urea SCR system, and its emission characteristic including particle is analyzed and evaluated against its regulation. This evaluation is performed for the diesel engine using ELPI(Electric Low Pressure Impactor) under the condition of constant engine RPM and load, and injecting urea solution to SCR system, particle number distribution of particle range from 7nm to 10μm was estimated.

This paper reports the results of an exhaust emissions characterization from the non-catalyst control systems employed on the Mazda RX-4 rotary, the Honda CVCC, and the Chrysler electronic lean burn. Throughout the paper, exhaust emissions from these vehicles are compared to those from a Chrysler equipped with an oxidation catalyst and an air pump. The emissions characterized are carbon monoxide, hydrocarbons, nitrogen oxides, sulfur dioxide, sulfates, hydrogen sulfide, carbonyl sulfide, hydrogen cyanide, aldehydes, particulate matter, and detailed hydrocarbons. A brief description of the sampling and analysis procedures used is included within the discussion.

The benefits of diesel fuel additives have been demonstrated in a broad range of performance and operational areas, from the refinery, through storage and distribution, to fuel dispensing and vehicle operation. The customer is certainly aware of their effects on fuel performance in many of these respects, such as cold-weather operation, ease of starting, foaming, odour, etc. An area of particular interest in customer perception, however, is fuel economy. Excluding the use of after-market fuel-treatment devices, it is claimed that additives of different types can improve fuel economy, for example by improving combustion, by maintaining injection equipment in optimum condition, or by reducing engine frictional losses.

In practical applications of ammonia SCR aftertreatment systems using urea as the reductant storage compound, one major difficulty is the often constrained packaging envelope. As a consequence, complete mixing of the urea solution into the exhaust gas stream as well as uniform flow and reductant distribution profiles across the catalyst inlet face are difficult to achieve. This paper discusses a modeling approach, where a combination of 3D CFD and a lumped parameter SCR model enables the prediction of system performance, even with non-uniform exhaust flow and ammonia distribution profiles. From the urea injection nozzle to SCR catalyst exit, each step in the modeling process is described and validated individually. Finally the modeling approach was applied to a design study where the performance of a range of urea-exhaust gas mixing sections was evaluated.

The paper discusses the concept, specification and overall performance of a 10 kW electric power range extender suitable for electric plug-in and series hybrid vehicles, based on a single cylinder, high speed, four stroke internal combustion engine, tested and developed at Istituto Motori CNR of Italy. This unit has been conceived from the beginning as a compact on board recharging system for the mentioned kind of means, and especially for city cars and small commercial vehicles. The paper starts by defining some characteristics, advantages and drawbacks of an electric city car, followed by the criteria adopted to characterize the nominal power of the range extender. Then, the ratio which leaded to the adoption of a single cylinder internal combustion engine is discussed, followed by an explanation of the main design characteristics of the whole unit.

A compact exhaust gas temperature control unit is presented. The unit was fitted to a gasoline direct injection production car together with a modified exhaust system. It was shown that it was possible to keep the exhaust gas temperature within the lean operational NOx temperature window of typical NOx absorption catalysts for the whole European drive cycle. This should improve the lean NOx conversion of such a catalyst system significantly. It was shown that the standard vehicle cooling system should be able to cope with the additional heat input from the temperature control unit without major modifications.