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An essential feature of the Audi Quattro permanent four-wheel drive system is in the inter-axle differential located on the hollow output shaft in the gearbox: the drive is taken from this differential forward to the front differential through the inside of the hollow shaft, and rearward to a propellor shaft driving the rear differential. The major advantages in everyday driving include improved traction and a reduced tendency toward throttle induced changes of attitude. The greater traction allows not only better progress in difficult road conditions; it also gives better acceleration in difficult traffic situations, such as when joining a busy main road. The more easily predictable handling response to throttle changes means that Quattro vehicles have better tracking stability. Altogether, the active safety and "roadability" are considerably improved.

There is a definite trend toward the increasing use of “Glass Encapsulation Technology” in the automotive industry. In this technology a glass object such as a window is placed within a mould and an elastomer is injected around the window giving a tight sealing system. A wide variety of materials are currently used as the sealing materials in either static or semi-static encapsulated glazing systems, including a wide range of “elastomers”. New thermoplastic elastomer compounds are being developed that are characterized by their consistent properties; including high melt-fluidity, very good surface appearance, sealing properties, and resistance to weathering. Compound performance is highly dependent on formulation variables as well as the chemistries of the base materials. KRATON® SEBS polymers1 are block copolymers of styrene and ethylene/butylene.

Limited and non-regulated emissions of scooters were analysed during several annual research programs of the Swiss Federal Office of Environment (BAFU) *). Small scooters, which are very much used in the congested centers of several cities, are a remarkable source of air pollution. Therefore every effort to reduce the emissions is an important contribution to improve the air quality in urban centers. In the present work detailed investigations of particle emissions of different 2-stroke scooters with direct injection and with carburettor were performed. The nanoparticulate emissions were measured by means of SMPS, (CPC) and NanoMet. Also the particle mass emission (PM) was measured with the same method as for Diesel engines. Extensive analyses of PM-residuum for SOF/INSOF, PAH and toxicity equivalence (TEQ), were carried out in an international project network. Particle mass emission (PM) of 2-S Scooters consists mostly of SOF.

(Paint) film as an alternative to spray applied paint has received growing attention in recent years. The potential for economic and environmental advantage and quality enhancement with this technology has been reported in several technical papers (Ref. 1, 3 and 4). The actual practice of film finishing, however, has received only limited notice. Film finishes have been applied to aluminum, stainless steel, PVC, and ABS. Starting in 1982, part applications include: wheel covers, door edge guards, window surrounds, roof drip moldings, lower windshield moldings, rocker panels, body side moldings, B pillars, and A pillars. Industry awareness and acceptance of film finishing as a viable alternative to spray applied paint is increasing. The two technologies are similar in many ways, yet distinctly different in other ways. They share a common goal: To yield a durable finish, economically and with superior visual impact. This paper reviews the unique aspects of film finishing.

The testing system developed will decrease the time and the costs involved in evaluating cylinder head valve bridge designs. The test uses actual data generated from engine testing to recreate the valve bridge cracks that occur during dynamometer and vehicle testing. This paper focuses on the system description, the test development, design modifications, and the test results obtained. Testing shows that this method correctly separates valve bridge designs by test cycle life using statistical methods. It is a cost effective and timely alternative to dynamometer testing.

In this paper, we present a design and control methodology of an innovated structure of switching synchronous motor. This control strategy is based on the pulse width modulation technique imposing currents sum of a continuous value and a value having a shape varying in phase opposition with respect to the variation of the inductances. This control technology can greatly reduce vibration of the entire system due to the strong fluctuation of the torque developed by the engine, generally characterizing switching synchronous motors. A systemic design and modelling program is developed. This program is validated following the implementation and the simulation of the control model in the simulation environment Matlab-Simulink. Simulation results are with good scientific level and encourage subsequently the industrialization of the global system.

This work deals with the CAE simulation of the behaviour of a belt employed in a CVT transmission of a large displacement scooter engine. Both FEM and MBS simulations were performed, in order to estimate the dynamic loads acting on the component and the stress state the belt is subject to. The MBS simulations were backed up by simple FEM tests performed in order to estimate the elastic properties of elementary portions of the belt. The MBS system comprised the belt and the two pulleys. As a result, the force components the pulleys exert on the belt were calculated. FEM non-linear analyses were performed in order to estimate the stress state the belt experiences. The belt's both manufacturing and working conditions were simulated.

Hybrid electric vehicles (HEVs) are worldwide recognized as one of the best and most immediate opportunities to solve the problems of fuel consumption, pollutant emissions and fossil fuels depletion, thanks to the high reliability of engines and the high efficiencies of motors. Moreover, as transport policy is becoming day by day stricter all over the world, moving people or goods efficiently and cheaply is the goal that all the main automobile manufacturers are trying to reach. In this context, the municipalities are performing their own action plans for public transport and the efforts in realizing high efficiency hybrid electric buses, could be supported by the local policies. For these reasons, the authors intend to propose an efficient control strategy for a hybrid electric bus, with a series architecture for the power-train.

Fuel efficiency and torque performance are two major challenges for highly downsized turbocharged engines. However, the inherent characteristics of the turbocharged SI engine such as negative PMEP, knock sensitivity and poor transient performance significantly limit its maximum potential. Conventional ways of improving the problems above normally concentrate solely on the engine side or turbocharger side leaving the exhaust manifold in between ignored. This paper investigates this neglected area by highlighting a novel means of gas exchange process. Divided Exhaust Period (DEP) is an alternative way of accomplishing the gas exchange process in turbocharged engines. The DEP concept engine features two exhaust valves but with separated function. The blow-down valve acts like a traditional turbocharged exhaust valve to evacuate the first portion of the exhaust gas to the turbine.

The battery cooling system is one of the most critical parts for the safe and efficient operation of the Li-ion battery pack in EVs. Battery liquid cooling system is most commonly used. This paper represents a comprehensive study of the electric vehicle battery liquid cooling system design and performance using the 1D tool and experimental validation. The 1D model includes the battery thermal load, cooling system components, and different ambient conditions. The cooling system components are calibrated using the experimental performance data of the components. The 1D model is used to evaluate the effect of fan speed, ambient temperature, compressor speed, and coolant flow rate on the battery cooling system and to optimize the component sizing. The results are then experimentally validated in a climate chamber, and the simulation results show good agreement with experimental results. The study's findings provide a good understanding of the Li-ion liquid cooling system.

The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.

This paper describes the potential motorcycle application of a parallel hybrid powertrain that was conceptualized, designed, developed and tested (for passenger car application) at Southwest Research Institute (SwRI). The patented powertrain mechanical layout and controller are described in this paper. The transitioning between operating modes has been analyzed for satisfactory performance. Initial fuel consumption simulations of the parallel hybrid drivetrain indicate more than double the fuel economy of an equivalent-size conventional drivetrain. The model has been previously validated on a passenger vehicle-sized prototype. The Southwest Research Institute inventors have been recently awarded U.S. Patent 6,110,066 for the parallel hybrid drivetrain.

A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

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.

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.

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.

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.

Aerospace structures manufacturers find themselves frequently engaged in large-scale 3D metrology operations, conducting precision measurements over a volume expressed in meters or tens of meters. Such measurements are often done by metrologists or other measurement experts and may be done in a somewhat ad-hoc fashion, i.e., executed in the most appropriate method according to the lights of the individual conducting the measurement. This approach is certainly flexible but there are arguments for invoking a more rigorous process. Production processes, in particular, demand an automated process for all such “routine” measurements. Automated metrology offers a number of advantages including enabling data configuration management, de-skilling of operation, real time input data error checking, enforcement of standards, consistent process execution and automated data archiving. It also reduces training, setup time, data manipulation and analysis time and improves reporting.