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An advanced low heat rejection engine concept has successfully completed a 100 hour endurance test. The combustion chamber components were insulated with thermal barrier coatings. The engine components included a titanium piston, titanium headface plate, titanium cylinder liner insert, M2 steel valve guides and monolithic zirconia valve seat inserts. The tribological system was composed of a ceramic chrome oxide coated cylinder liner, chrome carbide coated piston rings and an advanced polyolester class lubricant. The top piston compression ring Included a novel design feature to provide self-cleaning of ring groove lubricant deposits to prevent ring face scuffing. The prototype test engine demonstrated 52 percent reduction in radiator heat rejection with reduced intake air aftercooling and strategic forced oil cooling.

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 problem of testing large gas turbines at full load in the factory has been solved with the construction of a load test facility utilizing a gas turbine compressor as the load absorption device. Design philosophy and features are reviewed, and a summary, of operating experience to date is presented.

Two Cummins B5.9L engines were fueled with 100% biodiesel in excess of 48 months by the Agricultural Engineering Department at the University of Missouri-Columbia. The engines used to power Dodge pickups. The engine lubricating oil was sampled at 1000 mile intervals for analysis. Statistical analysis of the engine lubricating oil indicated that the wear metal levels in the lubricating oil were normal. A reduction in power was noted when the engines were tested using a chassis dynamometer. The 1991 pickup has been driven 110,451 km and the 1992 pickup has been driven approximately 177,022 km. The pickups averaged 6.9 km/L. Engine fuel efficiency and material compatibility issues are addressed in the paper.

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.

Up to now, various compressor models for automotive air conditioners have been manufactured to answer the needs of car manufacturers for fuel economy and quietness. The 10PC20 compressor, developed for automotive air conditioners, is the world's first swash plate type compressor having a continuously variable displacement mechanism. The 10PC20 is aimed at realizing a large displacement compressor with a continuously variable displacement mechanism, which has not been achieved until today. To achieve this goal, the 10PC20 design is based on the swash plate type compressor, consisting of double-headed pistons, which is adaptable to a large displacement and has excellent rotating balance and durability. The 10PC20 changes its displacement continuously by changing the inclination of the swash plate (swash plate angle) continuously. (See photo. 1 and 2) The 10PC20 adopts two variable displacement principles.

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.

A drivetrain model incorporating detailed crankshaft and drivetrain dynamics has been incorporated into an unsteady gas dynamic computer simulation of a single-cylinder two-stroke engine. This study examines the change in predicted engine performance caused by relaxing the conventional assumption of constant crankshaft velocity, and a comparison of results is presented. Relaxing the assumption changed the predicted brake mean effective pressures by over 10%. Experimental validation of the simulation involved mounting an engine to a test bed and driving an inertia wheel through a fully characterized drivetrain. A high-speed data acquisition system measured signals from a position encoder mounted on the crankshaft and from a non-contact torque transducer. The time and position data were used to calculate instantaneous crankshaft speed, and these results were compared to the predicted profiles. Simulation results and experimental measurements are presented and discussed.

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.

Transfer path analysis is a powerful tool to support the vehicle NVH development. On the one hand it is a fast method to gain an overview of the complex interplay in the vehicle noise generation process. On the other hand it can be used to identify critical noise paths and vehicle components responsible for specific noise phenomena. FEV has developed several tools, which are adapted to the considered noise phenomena: Powertrain induced interior noise and vibration is analyzed by VINS (Vehicle Interior Noise Simulation), which allows the deduction of improvement measures fast enough for application in the accelerated vehicle development process. Further on vehicle/powertrain combinations not realized in hardware can be evaluated by virtual installation of the powertrain in the vehicle, which is especially interesting in the context of engine downsizing from four to three or six to four cylinders.

Two-phase capillary loops are being extensively studied as heat collection and rejection systems for space applications as they appear to satisfy several requirements like low weight, low volume, temperature control under variable heat loads and/or heat sink, operation under on ground and micro gravity conditions, simplicity of mounting and heat transfer through tortuous paths. In 1998–2000 Alenia defined and Lavochkin Association developed the Deployable Radiator on the base of honeycomb panels, axial grooved heat pipes and Loop Heat Pipe. It was designed for on-ground testing.

Direct fuel injection is becoming mandatory in two-stroke S.I. engines, since it prevents one of the major problems of these engines, that is fuel loss from the exhaust port. Another important problem is combustion irregularity at light loads, due to excessive presence of residual gas in the charge, and can be solved by charge stratification. High-pressure liquid fuel injection is able to control the mixing process inside the cylinder for getting either stratified charge at partial loads or quasi-stoichiometric conditions, as it is required at full load. This paper shows the development of this solution for a small engine for moped and light scooter, using numeric and experimental tools. In order to obtain the best charge characteristics at every load and engine speed, different combustion chambers have been conceived and studied, examining the effects of combustion chamber geometry, together with injector position and injection timing

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.

In a running engine, various impacts are excitation sources for structural vibrations and engine noises. Engine noises are classified, depending on their excitation sources, into the combustion noise, the combustion induced mechanical noise and the mechanical noise. It is difficult to measure such noises separately because some impacts occur closely in time and space. In this paper, a transient noise generation model of an engine was proposed considering vibration and its damping of engine structure. The present model was verified through the single explosion excitation experiment for a stationary engine. Using the noise generation model, the combustion noise was separated from the total noise radiating from a running four-stroke gasoline engine for motorcycles. It was found that the combustion noise had larger power at lower frequencies than higher frequencies. However, its contribution to the total engine noise was relatively small.

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 cooperative road tests carried out during 1941 have added considerable information and experience to that already existing on the subject of road detonation testing. Extensive data were obtained on the fuel requirements of the 1940 and 1941 models of the three most popular cars. Corresponding data were obtained on the knocking characteristics of current gasolines representing the bulk of the sales volume in various parts of the United States. On account of large variations in octane-number requirement among different cars of the same make - due to differences in ignition timing, combustion-chamber deposit, and other causes - and on account of variations in commercial gasolines, it has been necessary to use statistical methods of analysis in the appraisal of fuel and engine relationships. These methods of analysis have been applied in a number of ways, and have proved very useful.