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In recent years, improvements in the fuel economy and exhaust emission performance of internal combustion engines have been increasingly required by regulatory agencies. One of the salient concerns regarding general purpose engines is the larger amount of CO emissions with which they are associated, compared with CO emissions from automobile engines. To reduce CO and other exhaust emissions while maintaining high fuel efficiency, the optimization of total engine system, including various design parameters, is essential. In the engine system optimization process, cycle simulation using 0-D and 1-D engine models are highly useful. To define an optimum design, the model used for the cycle simulation must be capable of predicting the effects of various parameters on the engine performance. In this study, a model for predicting the performance of a general purpose SI (Spark Ignited) engine is developed based on the commercially available engine simulation software, GT-POWER.

We present the effect of EGR, at a set fuel flow rate and intake temperature, on the operating parameters of timing of combustion, duration of combustion, power output, thermal efficiency, and NOx emission; which is remarkably low. We find that addition of EGR at constant inlet temperature and constant fuel flow rate has little effect on HCCI parameter of start of combustion (SOC). However, burn duration is highly dependent on the amount of EGR inducted. The experimental setup at UC Berkeley uses a 1.9-liter 4-cylinder diesel engine with a compression ratio of 18.8:1 (offered on a 1995 VW Passat TDI). The engine was converted to run in HCCI mode by addition of an 18kW air pre-heater installed in the intake system. Pressure traces were obtained using four water-cooled quartz pressure transducers, which replaced the Diesel fuel injectors. Gaseous fuel (propane or butane) flowed steadily into the intake manifold.

Advanced Vehicle Technologies (AVT), a Ballarat Australia based company, has developed the World's first diesel to 100% LPG conversion for heavy haul trucks. There is no diesel required or utilized on the trucks. The engine is converted with minimal changes into a spark ignition engine with equivalent power and torque of the diesel. The patented technology is now deployed in 2 Mercedes Actros trucks. The power output in engine dynamometer testing exceeds that of the diesel (in excess of 370 kW power and 2700 Nm torque). In on-road application the power curve is matched to the diesel specifications to avoid potential downstream power-train stress. Testing at the Department of Transport Energy & Infrastructure, Regency Park, SA have shown the Euro 3 truck converted to LPG is between Euro 4 and Euro 5 NOx levels, CO2 levels 10% better than diesel on DT80 test and about even with diesel on CUEDC tests.

The increased use of recycled resins can create a dilemma for automotive designers. On the one hand, there is a growing initiative to increase recycled materials content on vehicles, globally. On the other hand, traditional methods of recycling polymeric materials -both thermoplastics and thermosets - can lead to degradation of engineering, mechanical, processing, and / or aesthetic properties of the resin. In an era where quality rules, this situation forces designers to accept a much lower percentage of recyclate than they might otherwise wish to use or risk unacceptable property loss in molded parts - something no automaker can “afford ” for long. Hence, a valuable feedstream of materials (polymers) often ends up destined for a landfill once many consumer products are broken down and more easily reusable or recyclable materials are salvaged. As a case in point, each passenger car built globally contains an average of 15 - 20 kg of nylon polymers.

Nine identical 40-ft. transit buses were operated on B20 and diesel for a period of two years - five of the buses operated exclusively on B20 (20% biodiesel blend) and the other four on petroleum diesel. The buses were model year 2000 Orion V equipped with Cummins ISM engines, and all operated on the same bus route. Each bus accumulated about 100,000 miles over the course of the study. B20 buses were compared to the petroleum diesel buses in terms of fuel economy, vehicle maintenance cost, road calls, and emissions. There was no difference between the on-road average fuel economy of the two groups (4.41 mpg) based on the in-use data, however laboratory testing revealed a nearly 2% reduction in fuel economy for the B20 vehicles. Engine and fuel system related maintenance costs were nearly identical for the two groups until the final month of the study.

An integration study was performed coupling an SP-100 reactor with either a Brayton or Stirling power conversion subsystem. A power level of 100 kWe was selected for the study. The power system was to be compatible with both the lunar and Mars surface environment and require no site preparation. In addition, the reactor was to have integral shielding and be completely self-contained, including its own auxiliary power for start-up. Initial reliability studies were performed to determine power conversion redundancy and engine module size. Previous studies were used to select the power conversion optimum operating conditions (ratio of hot-side temperature to cold-side temperature). Results of the study indicated that either the Brayton or Stirling power conversion subsystems could be integrated with the SP-100 reactor for either a lunar or Mars surface power application.

A prototype 2007 ISL Cummins diesel engine equipped with a diesel oxidation catalyst (DOC), diesel particle filter (DPF), variable geometry turbocharger (VGT), and cooled exhaust gas recirculation (EGR) was tested at Southwest Research Institute (SwRI) under a high-load accelerated durability cycle for 1000 hours with B20 soy-based biodiesel blends and ultra-low sulfur diesel (ULSD) fuel to determine the impact of B20 on engine durability, performance, emissions, and fuel consumption. At the completion of the 1000-hour test, a thorough engine teardown evaluation of the overhead, power transfer, cylinder, cooling, lube, air handling, gaskets, aftertreatment, and fuel system parts was performed. The engine operated successfully with no biodiesel-related failures. Results indicate that engine performance was essentially the same when tested at 125 and 1000 hours of accumulated durability operation.

The trend towards battery voltage vacuum fluorescent displays continues the technological advances in design and construction of VFD's, as they are applied to the automobile environment. With the ever increasing use of electronic displays for electronically tuned radios (ETR's), compact disc (CD) players, and other entertainment systems, advances in battery voltage displays and their associated drive circuitry have become a necessity. With the inherent advantages of low voltage operation and high information density, VFD's will continue to dominate the automobile audio markets. This paper will discuss battery voltage displays, the basic circuitry necessary to operate a vacuum fluorescent display, and comment on the “off the shelf” controller and driver circuitry available.

In many countries of the world, carburetor motorcycles are the major transportation system for people. The large volumes of these motorcycles contribute to high levels of urban emissions and this fact promotes the relevant emissions regulations to become more stringent. This paper presents an approach to satisfy various new emissions regulations such as Euro-III and Taiwan 4th generation emissions regulations by optimizing the 4-stroke PFI (Port Fuel Injection) engine management system (EMS) and after-treatment system.

This paper shows some aspects of the automotive voltage energy system level shift from 14 to 42 Volts. New features and prospective emissions/fuel economy requirements are creating electrical power needs in future automobiles, which today's conventional system cannot adequately supply at 14 Vdc (nominal, with a 12 Volt battery). It will be necessary to provide electric motors, DC/DC converters, inverters, battery management, and other electronic controls to meet higher voltage requirements. Suppliers must now include 42 Volt components and systems within their product range and make these new components as light, small, and cost efficient as possible. This paper is a compilation of several published works aiming to offer a synthesis to introduce this subject to the Brazilian Automotive Market.

The characteristics of the combustion process in an improved design of a novel spark ignition engine studied by means of Computational Fluid Dynamics are presented. The engine is designed to work at low average combustion temperatures to achieve very low NOx emissions. The engine is a two-stroke, two piston in-line engine. The main combustion occurs in four combustion pre-chambers that have an annular shape with a nozzle on the side facing the cylinder. Fuel is directly injected into the pre-chambers by using high-pressure fuel injectors. A progressive burning process is expected to keep the flame inside the pre-chambers while the fast ejection of combustion products should produce effective mixing with the cold air in the cylinder. This fast dilution should guarantee a temperature drop of the combustion products thus reducing the formation of NOx via a thermal path.

Homogeneous Charge Compression Ignition (HCCI) is good method to be higher efficiency and to reduce NOx emission and particular matter together than conventional SI combustion engine. But HCCI depends on chemical reaction of fuel and air mixture. So controlling of ignition timing is difficult, and HCCI is high THC and CO emissions because temperature can't reach the enough temperature to reduce those. In this study, we investigated factor for auto ignition timing and combustion completion on n-Butane/Air mixture by a two-stroke HCCI engine. Auto Ignition temperature are known to be decided by fuel(1), for n-Butane, the temperature was 1150±30K. And as we researched combustion completion from In-cylinder gas temperature, increasing In-cylinder gas temperature caused high combustion efficiency and low THC, CO emissions.

Engines and fuels for transport as well as off-road applications are facing a double challenge: bring local pollution to the level requested by the most stringent city air quality standard reduce CO2 emission in order to minimize the global warming risk. These goals stimulate new developments both of conventional and alternative engines and fuels technologies. New combustion processes known as Controlled Auto-Ignition (CAI™) for gasoline engine and Homogeneous Charge Compression Ignition (HCCI) for Diesel engine are the subject of extensive research world wide and particularly at IFP for various applications such as passenger cars, heavy-duty trucks and buses as well as small engines. Because of the thermo-chemistry of the charge, the thermal NOx formation and the soot production are in principle much lower than in flames typical of conventional engines.

The challenge for the diesel engines today is to reduce harmful emissions, such as particulate matter (PM) and Nitrogen oxides (NOx), and enhance the fuel efficiency and power, which are its main advantages. To meet this challenge, DENSO has developed an advanced common rail system (CRS) that uses piezo actuated fuel injectors capable of delivering up to five injection events per combustion cycle at 180MPa, currently the world's highest commercially available diesel fuel injection pressure. The DENSO piezo injector incorporates an internally developed piezoelectric element that energizes quicker than its solenoid counterpart, thereby reducing the transition time for the start and end of the fuel injection event. The piezoelectric element and unique passage structure of the DENSO injector combine to provide a highly reliable and responsive fuel injection event.

1 An all fiber-optic sensor has been developed to measure H2O mole fraction and gas temperature in an HCCI engine. This absorption-spectroscopy-based sensor utilizes a broad wavelength (1320 to 1380 nm) source (supercontinua generated by a microchip laser) and a series of fiber Bragg gratings (19 gratings centered on unique water absorption peaks) to track the formation and temperature of combustion water vapor. The spectral coverage of the system promises improved measurement accuracy over two-line diode-laser based systems. Meanwhile, the simplicity of the fiber Bragg grating chromatic dispersion approach significantly reduces the data reduction time and cost relative to previous supercontinuum-based sensors. The data provided by the system is expected to enhance studies of the chemical kinetics which govern HCCI ignition as well as HCCI modeling efforts.

The 1977 Clean Air Act Amendments allow the U.S. Environmental Protection Agency to set high altitude emission standards for 1981-83, but specify that any such standards may not be more stringent than comparable sea level standards -- relative to 1970 emission levels. Since available high altitude emission data from 1970 models were incomplete and controversial, the Motor Vehicle Manufacturers Association contracted with Automotive Testing Laboratories, Inc. to test a fleet of 25 1970 cars. Results of the test program showed average increases in emissions at Denver's altitude, compared to sea level, to be about 30% for evaporative HC, 57 to 60% for exhaust HC, 215 to 247% for CO and -46 to -47% for NOx. Corresponding HC and CO exhaust emission baselines would be 6.4 to 6.6 and 108 to 118 g/mi respectively.

Since 1978 Ford Motor Company has been surveying the fuel economy of employes who lease new light duty vehicles from the Company. Winter and summer survey data for the three years are analyzed and compared. Car results show a significant and steady increase in average on-road fuel economy over the three year period. The percent differential between EPA measured and actual on-road fuel economy has lessened substantially since 1978. Furthermore, the percent difference between EPA and on-road is essentially constant over the range of EPA values for each of the three years. Limited fuel economy results for 1980 trucks are also discussed.

A program of emission testing and carburetor adjustment to reduce the levels of hydrocarbons and carbon monoxide in the exhaust gases and to demonstrate fuel economy improvements was held in Charlottetown during the week of July 14 to 19, 1980. The program was a co-operative effort of the Centre of Energy Studies of the Technical University of Nova Scotia, the Mobile Sources Division of the Air Pollution Control Directorate, Environment Canada and the Prince Edward Island Energy Corporation. Five hundred and twenty vehicles were tested during the period. The program was well received by the public and indicated that only 32% of the vehicle fleet were within specification when initially tested. A large percentage of these vehicles were satisfactorily adjusted. Mailback record cards were used to obtain an indication of the improved fuel economy. The data suggests that a substantial saving in fuel can be attained through carburetor tuning for low exhaust emissions.

This paper addresses fuel economy standards that can be obtained in 1985 for two-wheel drive LDT's using existing technology. To estimate the fuel economy, the fleet of LDT's is first segmented into market classes based on the concept of utility. The 1985 sales share of each class is predicted from an extrapolation of current trends as well as published sales forecasts. The 1985 fuel economy of each market class is projected using 1) MY '80 truck technology and fuel economy as a baseline, 2) a regression equation that allows an estimate of fuel economy based on the weight, drag, and engine displacement, and 3) the addition of fuel-efficient technologies. Estimates of weight reduction and new model introduction within each market class were derived from published manufacturers' plans. Based on this methodology, this analysis concludes that a fleet fuel economy in excess of 24/25 mpg is feasible for 1985 without/with the use of diesel engines.

The Clean Air Act Amendments of 1990 have brought about wholesale changes in the mandated requirements for the EPA and states to bring clean air to the country. Of particular interest to the light and heavy duty truck and bus industry are the requirements for VOC reductions in Title I, the hazardous pollutant reductions requirements in Title III, and the new permitting scheme required under Title V of the Act. The inter-relationship of lower VOC coatings, hazardous pollutant reduction, and permitting requirements will be presented. Since the Act does not fully mesh these requirements, the pathways that coating suppliers and coating application facilities can use to come into compliance will be explored. Specific VOC content of conforming coatings will be presented, how they will impact application processes, and how hazardous air pollutant reductions can be achieved is explored.