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A laboratory wear test is used to evaluate the wear protection properties of new and used engine oils formulated for FFV service. Laboratory-blended mixtures of these oils with methanol and water have also been tested. The test consists of a steel ball rotating against three polished cast iron discs. Oil samples are obtained at periodic intervals from a fleet of 3.0L Taurus vehicles operating under controlled go-stop conditions. To account for the effects of fuel dilution, some oils are tested before and after a stripping procedure to eliminate gasoline, methanol and other volatile components. In addition to TAN and TBN measurements, a capillary electrophoresis technique is used to evaluate the formate content in the oils. The results suggest that wear properties of used FFV lubricants change significantly with their degree of usage.

The paper reports on the outcome of a still on-going joint-research project with the objective of establishing a demonstrator high speed direct injection (HSDI) diesel engine in a Sport Utility Vehicle (SUV) which allows to exploit the effectiveness of new engine and aftertreatment technologies for reducing exhaust emissions to future levels of US/EPA Tier 2 and Euro 4. This objective should be accomplished in three major steps: (1) reduce NOx by advanced engine technologies (cooled EGR, flexible high pressure common rail fuel injection system, adapted combustion system), (2) reduce particulates by the Continuous Regeneration Trap (CRT), and (3) reduce NOx further by a DeNOx aftertreatment technology. The current paper presents engine and vehicle results on step (1) and (2), and gives an outlook to step (3).

The variation of viscosity with temperature and shear rate plays an important role in the analysis of lubrication of automotive systems. In this paper, a method for predicting the viscosity of non-Newtonian fluids, such as multigrade engine oils, over a wide range of temperatures and shear rates is outlined. This expression determines viscosity parameters for shear thinning fluids in terms of easily measured viscosity values at some reference state. A comparison of predictions with experimental data suggests that viscosity for multigrade engine oils can be predicted to within experimental uncertainty. The proposed method can be used in assessing lubricant viscosity at shear rates greater than 106 s-1, which are beyond the capability of current laboratory instruments. A comparative study with multigrade oils shows that performance at very high shear rates cannot be accurately gauged from high temperature, high shear (HTHS) viscosity measurements.

A test cell was developed for evaluating a 6-speed automatic transmission. The target vehicle had an internal combustion 5.4L gasoline V8 engine. An electric dynamometer was used to closely simulate the engine characteristics. This included generating mean torque from the ECU engine map, with a transient capability of 10,000 rpm/second. Engine inertia was simulated with a transient capability of 20,000 rpm/second, and torque pulsation was simulated individually for each piston, with a transient capability of 50,000 rpm/second. Quantitative results are presented for the correlation between the engine driven and the dynamometer driven transmission performance over more than 60 test cycles. Concerns about using the virtual engine in validation testing are discussed, and related to the high frequency transient performance required from the electric dynamometer. Qualitative differences between the fueled engine and electric driven testing are presented.

The 2013 Ford Fusion will be launched with an optional automatic engine start-stop feature. To realize engine start-stop on a vehicle equipped with a conventional powertrain, there are two major challenges in the vehicle system controls. First, the propulsive torque delivery from a stopped engine has to be fast. The vehicle launch delay has to be minimized such that the corporate vehicle attributes can be met. Second, the fuel economy improvement offered by this technology has to justify the cost associated with it. In pursuing fuel economy, the driver's comfort and convenience should be minimally impacted. To tackle these challenges, a vehicle system control strategy has been developed to accurately interpret the driver's intent, monitor the vehicle subsystem's power demands, schedule engine automatic stop and re-start, and coordinate the fast and smooth torque delivery to the wheels.

This paper explores the extent to which standard dilution tunnel measurements of motor vehicle exhaust particulate matter modify particle number and size. Steady state size distributions made directly at the tailpipe, using an ejector pump, are compared to dilution tunnel measurements for three configurations of transfer hose used to transport exhaust from the vehicle tailpipe to the dilution tunnel. For gasoline vehicles run at a steady 50 - 70 mph, ejector pump and dilution tunnel measurements give consistent results of particle size and number when using an uninsulated stainless steel transfer hose. Both methods show particles in the 10 - 100 nm range at tailpipe concentrations of the order of 104 particles/cm3.

Actual automotive themes in the beginning century are globalization and platform concepts. Platforms reduce manpower for basic power train development and enable a higher vehicle quality by sharing development cost to many models. New drive train generations with direct injected diesel and gasoline engines, variable valve train systems and hybrid drives require complex electronic control systems with many control parameters, which must be calibrated for each platform model to fulfill the targets for emissions, diagnostics and driveability. Calibration becomes a critical procedure in vehicle development. A negative effect of the platform is the reduced possibility to give a model or an OEM a brand specific driveability character, traditionally an important sales - promoting factor. The paper describes a tool for the objective real time assessment of vehicle driveability and vehicle character, using a new subjective - objective approach.

Intake and exhaust valve control has been combined with engine calibration control by an on-board computer to achieve a Variable Displacement Engine with improved BSFC during part throttle operation. The advent of the on-board computer, with its ability to provide integrated algorithms for the fast accurate flexible control of the entire powertrain, has allowed practical application of the valve disabler mechanism. The engine calibration basis and the displacement selection criteria are discussed, as are the fuel economy, emissions and behavior of a research vehicle on selected drive cycles ( Metro, Highway and Steady State ). Additionally, the impact upon vehicle driveability and other related subsystems ( e.g., transmission ) is addressed.

As vehicle tailpipe emission levels decrease with improvements in emission control technology and reformulation of gasolines, exhaust hydrocarbon levels begin to approach the levels in ambient air. Hydrocarbon speciation at these low levels requires high sensitivity capillary gas chromatography methods. In this study, a mixture of “synthetic” exhaust was prepared at two concentration levels (approximately 5 ppm C and 10 ppm C), and was analyzed by the widely-used Auto/Oil Air Quality Improvement Research Program (AQIRP) Phase II (gas chromatography) speciation method with a sensitivity of 0.005 ppm C for individual species. The mixture at each concentration level, along with a sample of ambient air, was analyzed a total of 20 times on 10 separate days over a 2½ week period. Concentrations of total hydrocarbons (HCs) and individual species (using the AQIRP library) were measured; averages and standard deviations were calculated.

A series calculation methodology from the injector nozzle internal flow to the in-cylinder fuel spray and mixture formation in a diesel engine was developed. The present method was applied to a valve covered orifice (VCO) nozzle with the recent common rail injector system. The nozzle internal flow calculation using an Eulerian three-fluid model and a cavitation model was performed. The needle valve movement during the injection period was taken into account in this calculation. Inside the nozzle hole, cavitation appears at the nozzle hole inlet edge, and the cavitation region separates into two regions due to a secondary flow in the cross section, and it is distributed to the nozzle exit. Unsteady change of the secondary flow caused by needle movement affects the cavitation distribution in the nozzle hole, and the spread angle of the velocity vector at the nozzle exit.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.

During recent years several VVT devices have been developed, in order to improve either peak power and low end torque, or part load fuel consumption of SI engines. This paper describes an experimental activity, concerning the integration of a continuously variable cam phaser (CVCP), together with an intake port deactivation device, on a small 4 cylinder 16V engine. The target was to achieve significantly lower fuel consumption under normal driving conditions, compared to a standard MPFI application. A single hydraulic cam phaser is used to shift both the intake and the exhaust cams to retarded positions, at constant overlap. Thus, high EGR rates in the combustion chamber and late intake valve closure (“reverse Miller cycle”) are combined, in order to reduce pumping losses at part load.

To meet the future demands on internal combustion engines regarding efficiency emissions and durability all design parameters must be optimized together. As a result of progress in material engineering fuel injection technology turbo charging technology exhaust gas after treatment there arise a multiplicity of possible parameters, such as: design parameters (compression ratio, dimensioning depending on peak firing pressure and mean effective pressure), injection system (rate shaping, split injection, injection pressure, hole diameter), air management (turbo charging with or without VTG, EGR rate) combustion optimization (timing, air access ratio). The interaction of all these parameters can not be over-looked without simulation and optimization tools. This is valid for the concept layout, the optimization and the application process later on.

The feasibility of using experimentally determined flow fields at intake valve closing, IVC, as initial conditions for computing the in-cylinder flow dynamics during the compression stroke is demonstrated by means of a computer simulation of the overall approach. A commercial CFD code, STAR-CD, was used for this purpose. The study involved two steps. First, in order to establish a basis for comparison, the in-cylinder flow field throughout the intake and compression strokes, from intake valve opening, IVO, to top dead center, TDC, was computed for a simple engine geometry. Second, experimental initial conditions were simulated by randomly selecting and perturbing a set of velocity vectors from the computed flow field at IVC.

Direct-injection spark-ignition (DISI) engines have been investigated for many years but only recently have shown promise as a next generation gasoline engine technology. Much of this new enthusiasm is due to advances in the fuel injection system, which is now capable of producing a well-controlled spray with small droplets. A physical understanding of new combustion systems utilizing this technology is just beginning to occur. This analytical and experimental investigation with a research single-cylinder combustion system shows the benefits of in-cylinder gasoline injection versus injection of fuel into the intake port. Charge cooling with direct injection is shown to improve volumetric efficiency and reduce the mixture temperature at the time of ignition allowing operation with a higher compression ratio which improves the thermodynamic cycle efficiency.

The CBR (Controlled Burn Rate) technology for MPFI engines is known to enable the reduction of throttle losses of gasoline engines by high EGR (Exhaust Gas Recirculation) rates due to the dilution tolerance of the swirl charge motion system using port deactivation. Now a new aspect of CBR is being developed: extremely low emissions during and after cold start. This paper is focused on the combustion stability and low emission aspects of CBR technology. It is shown how engine out emissions and catalyst light off behavior of an engine can be significantly improved using port deactivation. The very stable combustion directly after engine start, extremely retarded ignition timings in combination with lean engine operation and open valve injection with minimized wall wetting lead to very low HC emissions and very high exhaust gas temperatures.

The paper describes a feasibility test program on a 2 liter, 4 cylinder DI/TCI passenger car engine operated on the new alternative fuel Dimethyl Ether (DME, CH3 - O - CH3) with the aim of demonstrating its potential of meeting ULEV emissions (0.2 g/mi NOx in the FTP 75 test cycle) when installed in a full size passenger car. Special attention is drawn to the fuel injection equipment (FIE) as well as combustion system requirements towards the reduction of NOx and combustion noise while keeping energetic fuel consumption at the level of the baseline DI/TCI diesel engine. FIE and combustion system parameters were optimized on the steady state dynamometer by variation of a number of parameters, such as rate of injection, number of nozzle holes, compression ratio, piston bowl shape and exhaust gas recirculation.

The demand for improved fuel economy and the request for Zero Emission within cities require complex powertrains with an increasing level of electrification already in a short-termed timeframe until 2025. According to general expectations the demand for Mild-Hybrid powertrains will increase significantly within a broad range of implementation through all vehicle classes as well as on electric vehicles with integrated Range Extender (RE) mainly for use in urban areas. Whereas Mild Hybrid Vehicles basically use downsized combustion engines at current technology level, vehicles with a high level of powertrain electrification allow significantly different internal combustion engine (ICE) concepts. At AVL, various engine concepts have been investigated and evaluated with respect to the key criteria for a Range Extender application. A Wankel rotary engine concept as well as an inline 2 cylinder gasoline engine turned out to be most promising.

This paper describes two types of dielectric-effect sensors that may be used as alternatives to a dielectric-effect sensor using a single capacitor. In the first type, three capacitors are mounted in a compact module inserted into a vehicle fuel line. The three capacitors are connected together to form an electrical pi-filter network. This approach provides a large variation of output signal as the fuel changes from gasoline to methanol. The sensor can be designed to operate in the 1 to 20 MHz frequency range. The second type of sensor investigated uses a resonant-cavity structure. Ordinarily, sensors based on resonant cavities are useful only if the operating frequency is several hundred MHz or higher. The high relative dielectric constant of methanol allows useful sensors to be built using relatively short lengths of metal tubing for the cavities. For example, a sensor built using a fuel rail only 38.7 cm long operated in a frequency range from 31 to 52 MHz.

Regarding concepts for naturally aspirated engines, the high potential for fuel economy of Gasoline Direct Injection can only partially be utilized within the constraints of current or future emission legislation like EURO III / IV or LEV/ULEV. Instead of an expected improvement of 20 - 25 % currently only 10 - 15% can be obtained by the engine alone without vehicle optimizations considering all limitations of high volume production. A detailed analysis reveals concrete measures for further improvement. The application of DI gasoline technology clearly favors the combination with other fuel efficient technologies like downsizing by turbocharging and the application of a variable effective compression ratio by intake valve timing variation. Using the flexibility of direct gasoline injection some deficiencies of these technologies can be eliminated.