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This paper describes the new inline 4-cylinder QR engine series that is available in 2.0-liter and 2.5-liter versions. The next-generation QR engine series incorporates new and improved technologies to provide an optimum balance of power, quietness and fuel economy. Its quiet operation results from the adoption of a compact balancer system and the reduced weight of major moving parts. Power and fuel economy have been enhanced by a two-stage cooling system, a continuous variable valve timing control system, a dual close coupled catalyst system, electronic throttle control and an improved direct-injection system. The latter includes an improved combustion chamber concept and improved fuel spray characteristics achieved by driving the injector by battery voltage. A lightweight and compact engine design has been achieved by adopting a high-pressure die cast aluminum cylinder block, resin intake manifold and rocker cover and a serpentine belt drive.

The design of the newly developed Toyota AZ series 4 cylinder engine has been optimized through both simulations and experiments to improve heat transfer, cooling water flow, vibration noise and other characteristics. The AZ engine was developed to achieve good power performance and significantly reduced vibration noise. The new engine meets the LEV regulations due to the improved combustion and optimized exhaust gas flow. A major reduction in friction has resulted in a significant improvement in fuel economy compared with conventional models. It also pioneered a newly developed resin gear drive balance shaft.

Fulfillment of SULEV standards without catalyst - this is a target engineers at IAV have been working on since the middle of the 1990s. The core of this development is an advanced steam engine with a high performance burner. This burner features extremely low raw pollutant emission. This paper describes new solutions that were found to solve the challenging tasks in the development of such an engine concept.

Engineers use phenomenological simulation models to determine engine performance. Using these models, we can predict with reasonable accuracy the heat release rate mechanism inside the engine cylinder, which enables us to obtain a prediction of the pressure history inside the engine cylinder. Using this value and the volume change rate of the combustion chamber, we can then estimate the indicated power output of the engine. However, in order to obtain the brake engine power output we must have an indication for the mechanical losses, a great part of which are friction losses. Up to now various correlations have been proposed that provide the frictional mean effective pressure as a function mainly of engine speed and load. These correlations have been obtained from the processing of experimental data, i.e. experimental values for the indicated and brake power output of engines.

The LEV II and EURO V legislation in 2007/2008 require a high conversion level for nitrogen oxides to meet the emission levels for diesel SUVs and trucks. Therefore, U.S. and European truck manufacturers are considering the introduction of urea SCR systems no later than model year 2005. The current SCR catalysts are based mainly on systems derived from stationary power plant applications. Therefore, improved washcoat based monolith catalysts were developed using standard types of formulations. These catalysts achieved high conversion levels similar to extruded systems in passenger car and truck test cycles. However, to meet further tightening of standards, a new class of catalysts was developed. These advanced type of catalytic coatings proved to be equivalent or even better than standard washcoat formulations. Results will be shown from ESC, MVEG and US-FTP 75 tests to illustrate the progress in catalyst design for urea SCR.

Water-emulsified diesel fuel technology has been proven to reduce nitrogen oxides (NOx) and particulate matter (PM) simultaneously at relatively low cost compared to other pollution-reducing strategies. While the mechanisms which result in these reductions have been postulated, the development of new analytical tools to measure in-cylinder soot formation using optically accessible engines can lead to a deeper understanding of combustion and the chemical and physical mechanisms when water is present during combustion. In this study, an optically accessible single cylinder engine was used to study how water brought into the combustion chamber via an emulsified fuel changes the combustion process and thereby reduces emissions. In-cylinder measurements of relative soot concentrations were used to determine the effect of water-emulsified fuel on soot formation.

For years, secondary air injection Systems have been used to reduce hydrocarbon exhaust emissions for a short period after engine cold start. In the beginning, passive secondary air systems were used, with the airflow driven by the pressure pulsations in the exhaust system. Since 1990, for most applications, active secondary air systems (i. e., systems where air is injected into the hot exhaust gases by a pump) have been employed. Secondary air injection into the hot exhaust gases is realized by a d-c motor driven turbine pump, i. e. a secondary air pump, and a control valve. Numerous factors, including raw engine emissions during cold start and warm up, driveability requirements and the need to adapt to different emissions legislation, dictate the use of secondary air injection systems. The development of other exhaust aftertreatment systems, e. g., close-coupled or heated catalysts as well as packaging and cost factors will influence the market penetration of secondary air systems.

A breakthrough catalyst technology utilizing new mixed metal oxides in conjunction with Platinum Group Metals has been developed. Stable synergies are designed into the catalyst washcoat that enable high performance and durability to be achieved at low Platinum Group Metal usage. Extensive vehicle data is reported on catalysts aged using a variety of high-temperature accelerated aging cycles. Vehicle performance at the LEV, ULEV and LEV-II levels is discussed in the context of unique calibration-catalyst interactions. Conclusions concerning further areas of improvement and future applications are also reviewed.

As a part of the FutureTruck 2000 advanced technology student vehicle competition sponsored by the US Department of Energy and General Motors, West Virginia University has converted a full-size sport utility vehicle into a high fuel efficiency, low emissions vehicle. The environmental impact of the Chevrolet Suburban SUV, in terms of both greenhouse gas emissions and exhaust emissions, was reduced through hybridization without losing any of the functionality and utility of the base vehicle. The approach taken was one of using a high efficiency, state-of-the-art direct injection, turbocharged diesel engine coupled to a high output electric traction motor for power assist and to recover regenerative braking energy. The vehicle employs a state-of-the-art combination lean NOx catalyst, oxidation catalyst and particulate filter to ensure low exhaust emissions.

The University of Maryland team converted a model year 2000 Chevrolet Suburban to an ethanol-fueled hybrid-electric vehicle (HEV) and tied for first place overall in the 2000 FutureTruck competition. Competition goals include a two-thirds reduction of greenhouse gas (GHG) emissions, a reduction of exhaust emissions to meet California ultra-low emissions vehicle (ULEV) Tier II standards, and an increase in fuel economy. These goals must be met without compromising the performance, amenities, safety, or ease of manufacture of the stock Suburban. The University of Maryland FutureTruck, Proteus, addresses the competition goals with a powertrain consisting of a General Motors 3.8-L V6 engine, a 75-kW (100 hp) SatCon electric motor, and a 336-V battery pack. Additionally, Proteus incorporates several emissions-reducing and energy-saving modifications; an advanced control strategy that is implemented through use of an on-board computer and an innovative hybrid-electric drive train.

This paper describes the motivation for developing hydrogen-fueled engines for use in hybrid electric vehicles of the future. The ultimate motivation for using hydrogen as an energy carrier is carbon management. However, air quality concerns also provide motivation for developing hydrogen-fueled vehicles. For this reason, we discuss the position of the hydrogen-powered hybrid vehicle within the California Air Resources Board requirement for Zero Emission Vehicles. We describe the expected performance of an electrical generation system powered by a four-stroke, spark-ignited, internal combustion engine for a hydrogen-powered hybrid vehicle. The data show that the engine-out emissions of NOx will allow the vehicle to operate below the Super Ultra-Low Emission Vehicle standard set by the California Air Resources Board. The engine can run on either hydrogen or blends of hydrogen and natural gas. The engine can be optimized for maximum efficiency with low emissions.

The recently developed KIVA-GA computer code was used in the current study to optimize the combustion chamber geometry of a heavy -duty diesel truck engine and a high-speed direct-injection (HSDI) small-bore diesel engine. KIVA-GA performs engine simulations within the framework of a genetic algorithm (GA) global optimization code. Design fitness was determined using a modified version of the KIVA-3V code, which calculates the spray, combustion, and emissions formation processes. The measure of design fitness includes NOx, unburned HC, and soot emissions, as well as fuel consumption. The simultaneous minimization of these factors was the ultimate goal. The KIVA-GA methodology was used to optimize the engine performance using nine input variables simultaneously. Three chamber geometry related variables were used along with six other variables, which were thought to have significant interaction with the chamber geometry.

In order to match catalyst OBDII conditions the common procedure is oven aging with air, which is not suitable for complete converter systems due to mantle corrosion. The goal was, therefore, to find an alternative procedure to ensure a defined catalyst aging that would match 1,75 times the emission standard and is also good for SULEV. The new procedure currently being developed allows the aging of metal and ceramic catalysts as well as complete catalyst systems. The paper will present the aging process, emission data of fresh and aged catalysts and the feedback to the test car OBDII system.

Dual-monolith converters containing Pd-only catalysts followed by Pt/Rh three-way catalysts (TWCs) provide effective emission solutions for NLEV and Tier IIa close-coupled dual-bank V-8 applications due to optimal hydrocarbon and NOx light-off, transient NOx control, and balance of precious metal (PGM) usage. Dual-catalyst [Pd +Pt/Rh] systems on a 5.3L V-8 LEV light truck vehicle were characterized as a function of PGM loading, catalyst technology, and substrate cell density. NLEV hydrocarbon emission control of the 6500 lb vehicle was optimal using dual 1.2L converters with each containing front ceria-free Pd catalysts coupled with rear Pt/Rh TWCs. Advanced non-air prototype calibrations coupled with reduced catalyst washcoat mass on 600cpsi/4mil substrate resulted in minimal Pd usage of ∼0.02 toz/vehicle due to achieving catalyst inlet temperatures of 350-400°C in <10 sec on both banks of the V-8 engine.

The ever increasing demands on combustion engines with regard to exhaust emissions and fuel consumption require the use of modern analytical methods. Especially optical measurement techniques have contributed a lot to the realization of complicated engine concepts. The disadvantages of complex measurement techniques are the expenditure of time and the necessary changes of the engine. This paper introduces a new practice oriented optical measurement technique with the aid of an example. With this technique it is possible to record the combustion process with a sampling rate of up to 200 kHz through a small drilling. Even quick events like knocking can be recorded. The combustion luminosity is watched through a special UV-capable borescope, transmitted to an array of photoelectric transformers and finally recorded as a flame figure. We will show an SI-engine which is limited by knocking.

The Quarter Wave Coaxial Cavity Resonator (QWCCR) plasma igniter is designed, from previous theoretical work, as an ignition source for an internal combustion engine. The present research has explored the implementation of the QWCCR into an internal combustion (IC) engine. The QWCCR design parameters of inner conductor length, loop geometry, and loop position were varied for two igniters of differing operating frequency. Variations of the QWCCR radio frequency (RF) parameters, as a function of engine geometry, were studied by placing the igniter in a combustion chamber and manually varying the crank position. Three identical igniters were fitted with dielectric inserts and the parameters were studied before and after ignition was sustained in a twin-cylinder engine. Optimal resonator geometries were determined. Radio frequency parameter invariance was found with respect to crank angle and piston distance. The first successful IC engine ignition using a QWCCR was achieved.

To reduce the amount of fuel vapor created in the fuel tank, we developed a variable-capacity, plastic bladder fuel tank that is efficient, reliable, and provides permeation prevention performance. This bladder fuel tank changes in shape and total capacity in accordance with the volume of fuel it holds. Thus, in contrast to the conventional fuel tank, it can dramatically reduce the amount of fuel vapor that is ordinarily created in the fuel tank while the vehicle is being refueled, parked, or driven. The bladder fuel tank has been adopted in the Vapor Reducing Fuel Tank System of the North American model Prius, a vehicle that operates under the Toyota Hybrid System (THS), which complies with the SULEV exhaust emission requirement. This paper primarily gives an outline of the technology for manufacturing the bladder fuel tank.

During the last years a great deal of efforts have been made to reduce pollutant emissions from Direct Injection Diesel Engines. The use of gaseous fuel as a supplement for liquid diesel fuel seems to be one solution towards these efforts. One of the fuels used is natural gas, which has a relatively high auto - ignition temperature and moreover it is an economical and clean burning fuel. The high auto - ignition temperature of natural gas is a serious advantage against other gaseous fuels since the compression ratio of most conventional diesel engines can be maintained. The main aspiration from the usage of dual fuel (liquid and gaseous one) combustion systems, is the reduction of particulate emissions. In the present work are given results of a theoretical investigation using a model developed for the simulation of gaseous fuel combustion processes in Dual Fuel Engines.

The recent emergence of production Gasoline Direct Fuel Injection (GDFI) engines into the world markets offers the promise of both improved fuel economy and emissions for 4-stroke Spark Ignition (SI) engines. However with all new technologies there are new challenges that accompany them. The subjects of fuel and intake system and combustion chamber deposits in Port Fuel Injected (PFI) SI engines are well researched and documented. Today only a small amount of specific research exists for GDFI engines [1,2,3,4]. In any case, based on available PFI deposit literature it is possible to make a number of observations about the likely GDFI fuel and intake system deposit issues and their effect on fuel economy, exhaust emissions and performance during a lifetime of service.

The direct injection (DI) gasoline engine has drawn considerable attention recently for energy savings and emission reductions. Compared with current port fuel injection (PFI) engines, DI engines are designed to have high specific power output, low fuel consumption and low emissions at the same time. Among others a feature of the DI gasoline engine is its capability to freely alter the state of combustion from homogeneous to stratified combustion at different load conditions. Engines with high power density such as the DI engine, are also prone to knock. To suppress engine knocking a flexible and precise combustion control mechanism is required. The paper being presented describes some of the characteristics required for spark plugs utilized in DI gasoline engines.