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The demands on future mobility concepts for private transport will be determined by three major trends: climate change, urbanization and demographic change. These trends also provide the basis for three main development goals: “zero emissions”, “intelligent mobility” and “zero accidents”. In combination with intelligent traffic concepts and driver assistance functions, electric mobility will make a vital contribution to implementing these goals. To nevertheless keep individual mobility affordable and safe, the complexity of the electrical/electronic architecture (E/E architecture) of today's vehicles must be significantly reduced. It must advance along the steps that avionics and industrial automation already took more than 20 years ago, i.e. it must adopt the structures and methods of modern information and communication technologies (ICT). The text below describes the motivation and idea for future E/E architectures and the potential which arises from changing them significantly.

The On-Board Distillation System (OBDS) extracts, from gasoline, a highly volatile crank fuel that enables simultaneous reduction of start-up fuel enrichment and significant ignition timing retard during cold-starting. In a previous paper we reported reductions in catalyst light-off time of >50% and THC emissions reductions >50% over Phase I of the FTP drive cycle. The research presented herein is a further development of the OBDS concept. For this work, OBDS was improved to yield higher-quality start-up fuel. The PCM calibration was changed as well, in order to improve the response to intake manifold pressure transients. The test vehicle was tested over the 3-phase FTP, with exhaust gases speciated to determine NMOG and exhaust toxics emissions. Also, the effectiveness of OBDS at generating a suitable starting fuel from a high driveability index test gasoline was evaluated.

Selective Catalytic Reduction (SCR) of Nitrogen Oxide (NOx) emissions using ammonia or a 32.5%-urea solution has been used for many years in a variety of stationary applications. These applications include but are not limited to coal fired power plants, gas turbines, diesel locomotives, marine engines, as well as other stationary diesel and non-diesel engine applications. Global emission limits for mobile heavy-duty diesel engines are becoming increasingly rigid. In response to this trend the diesel industry has begun testing and applying various emission control technologies to mobile applications. SCR is one such technology. Europe is the first major market to introduce SCR into the heavy-duty (class 8) as well as medium-duty (class 4-7) truck applications. The EURO4 standards (effective Oct. 2005/2006) and the EURO5 standard (effective 2008) favor SCR as the NOx reduction technology of choice in the European Union (EU).

A liquid fuelled, fuel cell auxiliary power unit (APU) can provide efficient, quiet and low pollution power for a variety of applications including commercial and military vehicles. Truck idling regulation, customer comfort or military “stealth” operation by using electrical power, require a device disconnected from the main diesel engine. The power can be utilized for air conditioning as well as other auxiliary systems found on board commercial trucks for driver comfort. In a military vehicle, this regulated power could be supplied to telecommunication and other computer equipment required for military operations. A system designed to be an add-on or retrofit solution using alternative fuel can have the potential to meet these requirements on the hundreds of thousands of existing vehicles currently in service or as optional equipment on a newly procured vehicle.

Previous research has shown that the homogeneous charge compression ignition (HCCI) combustion concept holds promise for reducing pollutants (i.e. NOx, soot) while maintaining high thermal efficiency. However, it can be difficult to control the operation of the HCCI engines even under steady state running conditions. Power density may also be limited if high inlet air temperatures are used for achieving ignition. A methodology using a small pilot quantity of diesel fuel injected during the compression stroke to improve the power density and operation control is considered in this paper. Multidimensional computations were carried out for an HCCI engine based on a CAT3401 engine. The computations show that the required initial temperature for ignition is reduced by about 70 K for the cases of the diesel pilot charge and a 25∼35% percent increase in power density was found for those cases without adversely impacting the NOx emissions.

Changing diesel engine emission requirements for 2002 have led many diesel engine manufacturers to incorporate cooled Exhaust Gas Recirculation, EGR, as a means of reducing NOx. This has resulted in higher levels of soot being present in used oils. This paper builds on earlier work with fresh oils and describes a study of the effect of highly sooted oils on the low temperature pumpability in diesel engines. Four experimental diesel engine oils, of varying MRV TP-1 viscosities, were run in a Mack T-8 engine to obtain a soot level ranging between 6.1 and 6.6%. These sooted oils were then run in a Cummins M11 engine installed in a low temperature cell. Times to lubricate critical engine components were measured at temperatures ranging between -10 °C and -25 °C. A clear correlation was established between the MRV TP-1 viscosity of a sooted oil and the time needed to lubricate critical engine components at a given test temperature.

The influence of adsorption and desorption processes on the non-thermal plasma enhanced catalytic reduction of NOx on NaZSM5- and Al2O3-based lean-NOx catalysts (Pt-NH4ZSM5, Cu-NaZSM5, Fe-NaZSM5, Pt-Al2O3, Pd-Al2O3, CuO-Al2O3, Ag-Al2O3) was investigated by temperature programmed reaction experiments in the temperature range from 100 °C to 600 °C. Dodecane was used as a reducing agent. Strong HC adsorption- and desorption effects were observed on the zeolite catalysts, which were not influenced by plasma-pretreatment. Adsorption of NO2 and desorption of NO occurred on Al2O3-based catalysts. By plasma-pretreatment adsorption of NO2 was induced at low temperatures. NOx-reduction rates of the catalysts Cu-NaZSM5, Fe-NaZSM5, and the Ag-Al2O3 were increased substantially by plasma-pretreatment. Both plasma-induced and catalytic oxidation of HCs were limiting factors of the NOx-reduction obtained on these catalysts.

The mining industry has requested large capacity haul trucks with low maintenance to improve operating costs. To satisfy this request, diesel-electric drive systems have evolved from DC to AC control systems. AC drive technology offers high efficiency, low maintenance costs, and many advanced features over DC and mechanical drive technology. The use of AC inverters introduces the possibility of high current spikes to the motor during a two or three phase short circuit. This failure mode results in a large negative torque being generated in the motor that resonates until the current dissipates. This paper studies the effects of this spike on the electrical and mechanical system covering both analytical and field test results.

More stringent emission legislation has been a driver for changes in the design of Heavy Duty Diesel engines since the 1980s. Optimization of the combustion processes has lead to significant reductions of exhaust emission levels over the years. However, in the year 2002, diesel engines in the USA will have to meet an even more stringent set of emission requirements. Expectations are that this will force most engine builders to incorporate Exhaust Gas Recirculation (EGR). Several studies of the impact of EGR on lubricant degradation have shown increased levels of contamination with soot particles and acidic components. Both of these could lead to changes in lubricant requirements. The industry is developing a new specification for diesel engine lubricants, PC-9, using test procedures incorporating engines with EGR.

Prototype selective catalytic reduction (SCR) systems using urea have been demonstrated on diesel trucks in Europe in recent years. In view of upcoming stringent emissions control standards for US HD diesel engines, urea-SCR is being evaluated by US engine and truck manufacturers. The authors and their companies have worked jointly on a project to develop, test, and demonstrate urea-SCR on a US HD diesel engine and Class-8 truck. A prototype urea-SCR system was applied to a 12-liter HD diesel engine. The engine model selected is rated at 350 bhp and is common for highway trucks. The only engine modifications were changes to the injection timing control map in order to better suit the application of the urea-SCR system. This paper details two demonstration phases of the project as follows. The first phase includes recent emissions cell tests using a new compact SCR catalyst and an engine calibration optimized for lower NOX.

The Institute of Transportation Studies at the University of California, Davis (ITS-Davis) has brought together a group of public and industrial partners to demonstrate and evaluate the Siemens-Westinghouse Urea-Selective Catalyst Reduction System (SINOx™). The SINOx System has the potential to generate major reductions in nitrogen oxides (NOx) and the volatile organic fraction (VOF) of particulate (PM) from heavy-duty diesel engines, without increasing fuel consumption and carbon dioxide (CO2) emissions. This demonstration began with engine bench testing at Detroit Diesel Corporation to calibrate the system to attain 1 g/bhp-hr NOx emissions in the transient portion of the US-FTP on a 1999 Series 60 engine that has a 4 g/bhp-hr emission level. The second phase of the project entails an on-highway demonstration of a set of ten, Freightliner Class 8 heavy-duty diesel vehicles. These vehicles are part of the Valley Material Transport fleet based in French Camp, California.

The potential of plasma enhanced selective catalytic reduction (PE-SCR) for Diesel-exhaust treatment at temperatures between 60 °C and 180 °C has been investigated in test bench measurements with a 1.9 liter 66 kW VW Passat TDI engine. Non-thermal plasmas were generated by pulsed electrical excitation of dielectric barrier discharge (DBD) modules each having a flow cross section of 9.5 cm2 and an electrode length of 26 cm. Monolithic V2O5-WO3/TiO2-catalysts with cell densities of 150 cpsi and 200 cpsi were used for selective catalytic reduction. First experiments were performed with a single DBD module and a catalyst volume of 3.5 liters. For temperatures between 100 °C and 160 °C and exhaust gas flow rates below 1200 liters (STP)/min NOx-reduction rates up to 14 g/h were obtained with an energy cost of about 20 Wh/g NOx. At larger gas flow rates NOx-reduction rates decreased even at higher temperatures.

The mechanisms of plasma enhanced selective catalytic reduction of NOx on a V2O5-WO3/TiO2-catalyst were investigated for temperatures between 100 °C and 200 °C by applying various analytical methods. In experiments with synthetic gas mixtures containing Ar instead of N2 as a carrier gas the formation of N2 as a main product and thus catalytic reduction of NOx in reactions with NH3 has been proven using mass spectroscopy. More detailed information on the reaction kinetics of NO-formation and removal induced by non-thermal plasmas has been obtained from experiments in gas mixtures containing isotopically marked 15NO. FTIR-absorption spectroscopy was applied to measure the concentrations of 14N- and 15N-containing molecules. Particles formed by the combined plasma- and catalytic treatment of Diesel exhaust with NH3 as reducing agent were analyzed by energy dispersive X-ray scattering. The spectra indicate, that mainly sulfur containing particles were formed.

This paper describes the procedures used to reduce the tonal noise of a class eight truck engine timing gear train that was initially found to be objectionable under idle operating conditions. Initial measurements showed that the objectionable sounds were related to the fundamental gear mesh frequency, and its second and third harmonics. Experimental and computational procedures used to study and trouble-shoot the problem include vibration and sound measurements, transmission error analysis of the gears under light load condition, and a dynamic analysis of the drive system. Detail applications of these techniques are described in this paper.

This paper describes improvements achieved with regard to the long term stability and the system integrability of a previously described thick film NOx sensor for gasoline lean burn and diesel applications. (1, 2, 3) Durability test up to 1000 hours consisting of a temperature cycle have been carried out by a stoichiometric operating gasoline engine test bench. The NOx sensor demonstrates the NOx output shift in terms of the NOx sensitivity less than 5 % on a model gas apparatus and ± 7 % measuring accuracy in practical operating condition on a diesel engine after 1000 hours that is equivalent to approximately 60K miles driving. The integration of the control electronics for the sensor in its connector is achieved for the sensitive measuring current in the μA-range or less on vehicle applications. The developed electronics functions closed-loop controls for a tip temperature and oxygen pumps as well as a diagnosis of sensor malfunctions.

Electronic control modules for engine control applications have an increasing number of power drivers. Most of them are switching in a PWM mode or synchronously with engine speed. Fast switching of load currents and voltages generates a noise in the lower AM band (150 kHz … 10 MHz) exceeding given limits for radiated emissions. The objective was to determine how the switching noise could be reduced by means of controlled current and/or voltage slopes. Finally ways were identified to implement appropriate voltage slope controls into a fully integrated quad low side driver ASIC. The paper will show results from practical measurements in the time and frequency domain as well as theoretical data to describe the switching behavior before and after implementation of the improvements A major result was that both current and voltage slope control are necessary to achieve best results. A special method of wave shaping was identified as the optimum.

Mack Trucks' E7 direct injection heavy-duty diesel engine is a four cycle, in-line six cylinder design. The 728 cu in. (12 1) engine is turbocharged and chassis mounted air-to-air aftercooled. The E7 is being introduced in 1989 with power ratings of 250 hp to 400 hp (186 kW to 298 kW) at 1700 to 1800 rpm, calibrated to 1990 EPA standards. Highlights of the E7 engine's design, development and performance are presented. Information is included which illustrates the strategies utilized to attain program goals of controlling weight and cost while extending power ratings, reducing emissions levels, and improving fuel economy, serviceability, durability and reliability.

Two ceramic monolith wall flow diesel particulate traps, incorporating a new split flow design with a base metal catalytic coating were tested on line haul highway trucks to investigate their performance characteristics. The trucks were equipped with a 300 HP turbocharged and after-cooled engine. After-cooler by-pass was used to effect the regeneration of the trap and an elapsed-time scheme was employed to control the regeneration process. Tests were terminated after one trap completed 147,500 miles of operation on the truck for in-depth examination of the trap to determine the cause of substantial increase in back pressure. Tests with the second trap of identical design was also terminated due to filtering efficiency loss, the cause of which was traced to a flaw in the canning arrangement. This arrangement permitted exhaust flow to by-pass the element and led to melt down of the trap, due to reduced flow during regeneration.

Knock limitations are investigated using natural gas, with diesel pilot ignition, as a fuel for the 3406 DI-TA Caterpillar diesel engine. Thermodynamic properties at TDC are generated by computer and compared with experimental results. Exhaust emissions are analyzed. A comparison is made of dual-fuel operation relative to diesel. Observations are made to determine the onset of knock. The onset of knock is characterized as a function of engine speed, load, inlet manifold temperature, and air-fuel ratio (A/F). The conditions at the onset of knock are determined using cylinder pressure data. The most efficient operating range is determined with knock avoidance as a prime parameter.

A foundation of highway truck ride and cab suspension historical evolution is laid describing the influence of marketplace demands, highway conditions, and government laws. Ride quality test methods are revealed along with variables tried and conclusions drawn. These data and techniques are then used to design cab suspension systems for a new line of truck products including both conventional and COE cabs.