Search Results

Diesel engines, especially CR (Common Rail) DI (Direct Injection) TCI (Turbo Charged Inter-cooled), share a wide acceptance in the passenger car market due to the enormous torque and flexibility at low engine speed. A pre - condition for the use of a diesel engine in a motorcycle is that the disadvantages like combustion noise and visible smoke are reduced or eliminated. Moreover the fuel economy and performance characteristics of a diesel engine are dedicated to be used in a touring or large displacement motorcycle. The AVL engine concept is the first high performance diesel engine to be specially designed for motorcycles in terms of packaging and styling. To compensate for the limited engine speed range a gearbox with a wide ratio spread is required. This leads to a manual transmission with at least 6 gears or an automatic transmission. For the AVL concept an AMT (Automated Manual Transmission) was selected.

Abstract The ASTM D130 was first issued in 1922 as a tentative standard for the detection of corrosive sulfur in gasoline. A clean copper strip was immersed in a sample of gasoline for three hours at 50°C with any corrosion or discoloration taken to indicate the presence of corrosive sulfur. Since that time, the method has undergone many revisions and has been applied to many petroleum products. Today, the ASTM D130 standard is the leading method used to determine the corrosiveness of various fuels, lubricants, and other hydrocarbon-based solutions to copper. The end-of-test strips are ranked using the ASTM Copper Strip Corrosion Standard Adjunct, a colored reproduction of copper strips characteristic of various degrees of sulfur-induced tarnish and corrosion, first introduced in 1954. This pragmatic approach to assessing potential corrosion concerns with copper hardware has served various industries well for a century.

General Motors Powertrain Division has developed the next generation big block V8 engine for introduction in the 1996 model year. In addition to meeting tighter emission and on-board diagnostic legislation, this engine evolved to meet both customer requirements and competitive challenges. Starting with the proven dependability of the time tested big block V8, goals were set to substantially increase the power, torque, fuel economy and overall pleaseability of GM's large load capacity gasoline engine. The need for this new engine to meet packaging requirements in many vehicle platforms, both truck and OEM, as well as a requirement for minimal additional heat rejection over the engine being replaced, placed additional constraints on the design.

General Motors Powertrain Group (GMPTG) has developed an all new small block V8 engine, designated LS1, for introduction into the 1997 Corvette. This engine was designed to meet both customer requirements and competitive challenges while also meeting the ever increasing legislated requirements of emissions and fuel economy. This 5.7L V8 provides increased power and torque while delivering higher fuel economy. In addition, improvements in both QRD and NVH characteristics were made while meeting packaging constraints and achieving significant mass reductions.

Urea-selective catalytic reduction (SCR) catalysts are the leading aftertreatment technology for diesel engines, but there are major challenges associated with meeting future NOx emission standards, especially under transient drive cycle conditions that include large swings in exhaust temperatures. Here we present a simplified, transient, one-dimensional integral model of NOx reduction by NH₃ on a commercial small-pore Cu-zeolite urea-SCR catalyst for which detailed kinetic parameters have not been published. The model was developed and validated using data acquired from bench reactor experiments on a monolith core, following a transient SCR reactor protocol. The protocol incorporates NH₃ storage, NH₃ oxidation, NO oxidation and three global SCR reactions under isothermal conditions, at three space velocities and at three NH₃/NOx ratios.

After the first appearance of LED rear lamps, which employed mainly two-dimensional arrays of LEDs, the request of stylists and OEMs to have three-dimensional LED alignment has increased strongly. Development of more powerful LEDs and new packaging and assembly technologies now allows for a three-dimensional assembly of the LEDs, giving an impression of depth and enabling the LEDs to follow even extreme curvatures. This gives great customer satisfaction in terms of styling, but the disadvantage is that the cost for the three-dimensional LED alignment increases significantly. To counteract this development, we have developed a light guide technology approach (so-called 2.5 D) to combine a cost efficient LED assembly process with the flexibility of a 3 D arrangement of the light sources. Thus, we can use standard planar FR4 (Flame Resistant 4) LED printed circuit boards with arbitrary LEDs and do not depend on a certain assembly technology.

Electrical Air Conditioning Systems for 42 V vehicles will provide many benefits in terms of Environment protection, car Architecture, cabin Comfort and overall Safety. E-A/C Systems essentially differ from conventional ones by the use of electrical compressors. First of all, they will be particularly well adapted to new powertrains, helping to make them more environmentally friendly. Accurate control and high efficiency under the most common thermal conditions will reduce the A/C impact on fuel consumption. Besides, higher sealing integrity will cut emissions of refrigerant during normal operation and maintenance. Secondly, the use of an electrically driven compressor (EDC) will suppress a belt, and will reduce the packaging constraints. This will help to design new vehicle architectures. Thirdly, the electrification of air conditioning will allow better thermal comfort. In particular, E-A/C Systems provide a good opportunity for cabin pre-conditioning.

A 2-D computational model was developed to describe the flow and filtration processes, in a honeycomb structured ceramic diesel particulate trap. This model describes the steady state trap loading, as well as the transient behavior of the flow and filtration processes. The theoretical model includes the effect of a copper fuel additive on trap loading and transient operation. The convective terms were based on a 2-D analytical flow field solution derived from the conservation of mass and momentum equations. The filtration theory incorporated in the time dependent numerical code included the diffusion, inertia, and direct interception mechanisms. Based on a measured upstream particle size distribution, using the filtration theory, the downstream particle size distribution was calculated. The theoretical filtration efficiency, based on particle size distribution, agreed very well (within 1%) with experimental data for a number of different cases.

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 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.

A unique heat exchanger has been developed with potential applications for cooling high power density electronics and perhaps high energy laser mirrors. The device was designed to absorb heat fluxes of approximately 50 w/cm2 (158,000 Btu/hr.ft2) with a low thermal resistance, a high surface temperature uniformity and very low hydraulic pumping power. A stack of thin copper orifice plates and spacers was bonded together and arranged to provide liquid jet impingement heat transfer on successive plates. This configuration resulted in effective heat transfer coefficients, based on the prime surface, of about 85,000 w/m2 °C (15,000 Btu/hr.ft2 °F) and 1.8 watts (.002 HP) hydraulic power with liquid Freon 11 as coolant.

A drag dynamometer was used to evaluate the performance of automotive brake drums made from four kinds of materials with different thermal conductivities. In the order of decreasing thermal conductivity they are chromium copper, aluminum/cast iron composite, cast iron, and nickel-aluminum bronze. All of the drums were of the standard configuration used in SAE J 661a, or closely approximated it. The drums were run in conjunction with three types of lining materials: nonabrasive, moderately abrasive, and highly abrasive. Temperatures near the lining/drum interface, coefficients of friction, and lining wear were measured and compared. For a given amount of work done, the temperature near the drum surface was found to be lowest for the chromium copper drums, with progressively higher temperatures in the aluminum/cast iron composite, nickel-aluminum bronze, and cast iron drums. Relative lining wear and coefficient of friction varied with the type of lining tested.

The effect of rotor alloy composition on thermal conditions in a disc brake system was determined analytically. The three alloys selected were gray cast iron, 356 aluminum, and copper -1% chromium. This study includes calculations of the temperature and heat storage in the various portions of the brake system, as well as the variations of convective heat transfer throughout the system. These computations were made for the transient conditions existing during a series of 60 mph stops (15 ft/sec2 deceleration). The steady-state rotor surface temperature and the thermal gradients were found to decrease with increasing thermal conductivity of the alloys. The rotor surface temperatures for the first two stops were relatively independent of thermal conductivity, but were strongly dependent on heat capacity. Convection was found to occur almost entirely (greater than 90%) from the rotor surface and ventilating passages.

This paper presents a computational study to investigate effects of crystal orientations on plasticity and damage of copper crystal at atomic scale. In the present study, a single crystal copper model was created as a target, which was struck and penetrated by a single crystal nickel. Three orientations, single slip system [1 0 1, 1 2 -1, -1 1 1], double slip system [1 1 2, 1 1 0, 1 1 -1], and octal slip system [1 0 0, 0 1 0, 0 0 1], were applied to the copper crystal. Their effects on plasticity and damage behavior of the single crystal copper were studied and compared using molecular dynamics simulations. Modified Embedded Atom Method potentials were applied to determine the pair interactions between the copper and nickel atoms.

This paper discusses the technology for disposal of diesel particulate by catalytic ignition and combustion. Using the trap-oxidizer concept, the collected soot was catalytically treated to make ignition and combustion more practical under diesel engine exhaust conditions. The catalyzed ignition was examined in a laboratory hot-tube reactor and the information thus obtained was used to design trials under engine exhaust conditions. Solutions of metal salts such as copper, manganese, or cobalt chlorides, or the corresponding nitrates, have been shown to be effective; most of this study was carried out using solutions of mixtures of copper chloride and sodium chloride. Suitable solvents included methanol, glycol-water mixtures, and distilled water. Soot-related parameters such as the soluble organic content, degree of compaction, graphitization, and surface area have been examined briefly during the course of the study.

This paper introduces for the first time a fully connectorized passive optical star for use with plastic optical fiber that addresses all automotive application requirements. A unique mixing element is presented that offers linear expandability, uniformity of insertion loss, and packaging flexibility. The star is constructed of all plastic molded components to make it low cost and produceable in high volume and is single-ended to facilitate vehicle integration. The star is connectorized to facilitate assembly into the vehicle power and signal distribution system.

Experience tells us that one can develop a technically comfortable seat where the seat fits and supports the occupant. The pressure distribution is optimized and the seat and packaging are such that a good posture is attainable by many. The dynamic characteristics of the seat and the vehicle are technically good. Despite all this the customer is not satisfied. Despite it being a technically comfortable seat, it does meet the customers' expectations and/or priorities and thus the comfort provided is lacking. This paper seeks to explore that gap between the seat and the user by modeling comfort using techniques similar to those found in the social sciences where models often focus on user or individual behavior. The model is built upon but diverges from the Cobb Douglas consumer utility model found in economics. It is presented as theory and presents a very different perspective on comfort.

This paper is a discussion of the relative merits of the front, mid and rear engined car concepts. After discussing some basic packaging considerations, and implications in respect of legislation, the authors make comparisons of performance potential in respect of traction and aerodynamics. Limiting power weight ratios are derived. Primary and secondary ride implications are reviewed and effects on braking are mentioned. Steering and cornering characteristics are assessed by first establishing correlation between prediction and measurement using actual vehicles. Means of simplifying the prediction of steady state steering characteristics are described. Two “model” cars of front and mid engined configuration are then used to predict the steady state and dynamic steering consequences of various specification changes and some conclusions are drawn as to inherent differences.

The increasing use of embedded electronics in aerospace and automotive vehicles increases the designers' concern regarding the reliability of the components as well as the reliability of their interconnections. The discussion about the most appropriate method for assessing the reliability of solder joints for a given application is an ever-present theme in the literature. Several methods of prediction have been developed for assessing the reliability of solder joints. The standard method established by the industries for assessing reliability of solder joints is the thermal cycling. However, when the thermal distributions in real applications are studied, particularly in some electronic components used in on-board electronics of space systems, the thermal cycling does not represent what actually happens in practice in the packaging.

The introduction of drive-by-wire systems into modern vehicles has generated new challenges for the designers of embedded systems. These systems, based primarily on microcontrollers, need to achieve very high levels of reliability and availability, but also have to satisfy the strict cost and packaging constraints of the automotive industry. Advances in VLSI technology have allowed the development of single-chip systems, but have also increased the rate of intermittent and transient faults that come as a result of the continuous shrinkage of the CMOS process feature size. This paper presents a low-cost, fault-tolerant system-on-chip architecture suitable for drive-by-wire and other safety-related applications, based on a triple-modular-redundancy configuration at the processor execution pipeline level.