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All around the world, steps are being taken to improve the quality of our environment. Prominent among these are the definition, implementation, and attainment of increasingly stringent emissions regulations for all types of engines, including off-highway diesels. These rigorous regulations have driven use of technologies like after-treatment, advanced air systems, and advanced fuel systems. Fuel dispensed off-highway is routinely and significantly dirtier than fuel from on-highway outlets. Furthermore, fuels used in developing countries can be up to 30 times dirtier than the average fuels in North America. Poor fuel cleanliness, coupled with the higher pressures and performance demands of modern fuel systems, create life challenges greater than encountered with cleaner fuels. This can result in costly disruption of operations, loss of productivity, and customer dissatisfaction in the off-highway market.

Some car shapes produce a substantial drag component from the generation of trailing vortices. This vortex (or lift dependent) drag is difficult to quantify for the whole vehicle, for reasons that are discussed. It has previously been shown that vortex drag may be assessed for some car features by consideration of the relationship between changes in drag and lift. In this paper this relationship is explored for some different vehicle shape characteristics, which produce positive and negative lift changes, and their combinations. Vortex drag factors are determined and vortex drag coefficients considered. An interference effect is identified between some of these features. For the simple bodies investigated the vortex drag contribution can be considerable.

For the vehicles with frequent stop-start operations, fuel consumption can be reduced significantly by implementing stop-start operation. As one way to realize this goal, the pneumatic hybrid technology converts kinetic energy to pneumatic energy by compressing air into air tanks installed on the vehicle. The compressed air can then be reused to drive an air starter to realize a regenerative stop-start function. Furthermore, the pneumatic hybrid can eliminate turbo-lag by injecting compressed air into manifold and a correspondingly larger amount of fuel into the cylinder to build-up full-load torque almost immediately. This paper takes the pneumatic hybrid engine as the research object, focusing on evaluating the improvement of fuel economy of multiple air tanks in different test cycles. Also theoretical analysis the benefits of extra boost on reducing turbo-lag to achieve better performance.

Traditionally, university research in engine technology has been focused on fundamental engine phenomena. Increasingly however, research topics are developing in the form of systems issues. Examples include air and exhaust gas recirculation (EGR) management, after-treatment systems, engine cooling, hybrid systems and energy recovery. This trend leads to the need for engine research to be conducted using currently available products and components that are re-configured or incrementally improved to support a particular research investigation. A production engine will include an electronic control unit (ECU) that must be understood and utilised or simply removed and circumvented. In general the intellectual property (IP) limitations places on ECUs by their suppliers mean that they cannot be used. The supplier of the ECU is usually unable to reveal any detail of the implementation. As a consequence any research using production hardware is seriously disadvantaged from the beginning.

To improve the state of the art in automotive aerodynamic prediction using CFD, it is important to compare different CFD methods, software and modelling for standardized test cases. This paper reports on the 2nd Automotive CFD Prediction Workshop for the Windsor body squareback test case. The Windsor model has high quality experimental data available and a simple geometry that allows it to be simulated with limited computational resources. The model is 1 metre long and operates at a Reynolds number of 2.7 million. The original Windsor model did not include wheels, but a second variant was added here with non-rotating wheels. Experimental data is available for integrated forces, surface pressure and wake PIV surveys. Eight standard meshes were provided, covering the two geometry variants, two near wall mesh spacings (relating to wall resolved and wall modelled) and two mesh densities in the wake (relating to RANS and eddy resolving).

A brief overview of the history and scope of the SAE Oil Labeling Assessment Program is presented. Then, the results of analyses on 893 samples of engine oil purchased in the retail market over the first three years of the program, are discussed. All samples were labeled with the API SF or SG Service Category, separately, or in combination with an API “C” category designation. Additionally, 43 engine oil samples found to be questionably labeled, were repurchased and analyzed; these results are included.

The results of analyses on 300 samples of engine oil purchased in the retail market in 1990 are discussed. All samples were labeled with the API SF or SG Service Category, separately, or in combination with an API C category designation. Also, 17 oils previously found to be questionably labeled, from the 1989 set, were repurchased and analyzed. These results are included.

China is the world’s largest automotive producer and has the world’s biggest automobile market. However, in the past decades, the development of China’s automotive industry has depended primarily on the foreign direct investment; domestic automakers have struggled in the lower ranks of car producers. In recent years, China’s automotive industry, supported by government policies, has been improving their Research and Development (R&D) capacity, to compete with their international peers. Against this background, China’s automotive industry requires a large number of R&D professionals who have not only a higher degree but also the applied and practical knowledge and skills of research. For the purpose of meeting the industry’s needs, a new Professional Automotive Engineering Masters Programme was launched in 2009, which aims to deliver the Masters to be the R&D professionals in the future.

The automotive industry is dramatically changing. Many automotive Original Equipment Manufacturers (OEMs) proposed new prototype models or concept vehicles to promote a green vehicle image. Non-traditional players bring many latest technologies in the Information Technology (IT) industry to the automotive industry. Typical vehicle’s characteristics became wider compared to those of vehicles a decade ago, and they include not only a driving range, mileage per gallon and acceleration rating, but also many features adopted in the IT industry, such as usability, connectivity, vehicle software upgrade capability and backward compatibility. Consumers expect the latest technology features in vehicles as they enjoy in using digital applications in laptops and mobile phones. These features create a huge challenge for a design of a new vehicle, especially for a human-machine-interface (HMI) system.

Relative velocity detection thresholds of drivers are one factor that determines their ability to avoid rear-end crashes. Laboratory, simulator and driving studies show that drivers could scale relative velocity when it exceeded the threshold of about 0.003 rad/sec. Studies using accident reconstruction have suggested that the threshold may be about ten times larger. This paper discusses this divergence and suggests reasons for it and concludes that the lower value should be used as a true measure of the psychological threshold for detection of relative velocity.

A new form of SAE Transactions has been developed which allows for considerable flexibility in format, content, and distribution. A key volume includes abstracts of all SAE papers and a comprehensive depth index. Optional additions include printed and bound sets of all Transactions papers in full, subscriptions for all SAE papers, subscriptions for all SAE Transactions papers, and microfiche versions of each of these. No longer limited by physical size, all worthy papers can now be included in Transactions together with discussion, thereby enlarging the scope of Transactions approximately seven times.

A review of many years of published work has shown that hydrogen embrittlement can occur under rolling contact conditions. Breakdown of lubrication and contamination with water have been cited as the probable sources of atomic hydrogen. In this paper, a unique fracture morphology is identified and the mechanism of the fracture progression from initiation to final catastrophic failure is proposed. Development of beneficial residual compressive stress near the contacting surfaces is one approach used to avoid this type of failure. Several alternative methods capable of developing a more desirable stress distribution will be discussed.

In this paper the effects of a rough underbody on the rear wake structure of a simplified squareback model (the Windsor model) is investigated using balance measurements, base pressure measurements and two and three component planar PIV. The work forms part of a larger study to develop understanding of the mechanisms that influence overall base pressure and hence the resulting aerodynamic drag. In the work reported in this paper the impact of a rough underbody on the base pressure and wake flow structures is quantified at three different ground clearances. The underbody roughness has been created through the addition of five roughness strips to the underbody of the model and the effects on the wake at ground clearances of 10.3%, 17.3% and 24.2% of the model height are assessed. All work has been carried out in the Loughborough University Large Wind Tunnel with a ¼ scale model giving a blockage ratio of 4.4% for a smooth under-body or 4.5% with the maximum thickness roughness strips.

China has become the world’s largest vehicle market in terms of sales volume. Automobiles sales keep growing in recent years despite the declining economic growth rate. Due to the increasing attention given to the environmental impact, more stringent emission regulations are being drafted to control traditional internal combustion engine emissions. In order to reduce vehicle emissions, environmentally-friendly new-energy vehicles, such as electric vehicles and plug-in hybrid vehicles, are being promoted by government policies. The Chinese government plans to boost sales of new-energy cars to account for about five percent of China’s total vehicle sales. It is well known that more electric and electronic components will be integrated into a vehicle platform during vehicle electrification.

The introduction of MultiAir technology [8] has had a strong impact on engine performance, fuel consumption, emissions and control. This technology, intended at first for gasoline engines and applied only on intake valves, is aiming at the reduction of engine breathing losses and, as a consequence, reduction of pollutant emissions and fuel consumption, together with an improvement of maximum intake efficiency. Further positive effects of MultiAir technology have been a significant improvement of Low End Torque, engine driveability (“fun-to-drive” index) and other operating conditions (e.g. idle control). Current development of MultiAir technology is focusing on a better management of hot EGR (Exhaust Gas Recirculation), still acting only on the intake side, although with specifically designed valve lift profiles. This application of MultiAir technology is pushing gasoline engines towards new levels of performance improvements.

Software systems on electronically controlled diesel truck engines typically provide diagnostic features to enable the engine mechanic to identify and debug system problems. As future systems become more sophisticated, so will the diagnostic requirements. The advantages of serviceability and accuracy found in todays electronic systems must not be allowed to degrade due to this increased sophistication. One method of maintaining a high level of serviceability and accuracy is to place an even greater priority on diagnostics and servicing in the initial design phase of the product than is done today. In particular, three major goals of future diagnostic systems should be separation of component failures from system failures, prognostication of failures and analysis of engine performance. This paper will discuss a system to realize these goals by dividing the diagnostic task into the Electronic System Diagnostics, Engine System Diagnostics and the Diagnostic Interface.

Sports Utility Vehicles (SUVs) typically have a blunt rear end shape (for design and practicality), however this is not beneficial for aerodynamic drag. Drag can be reduced by a number of passive and active methods such as tapering and blowing into the base. In an effort to combine these effects and to reduce the drag of a visually square geometry slots have been introduced in the upper side and roof trailing edges of a squareback geometry, to take air from the freestream and passively injects it into the base of the vehicle to effectively create a tapered body. This investigation has been conducted in the Loughborough University’s Large Wind Tunnel with the ¼ scale generic SUV model. The basic aerodynamic effect of a range of body tapers and straight slots have been assessed for 0° yaw. This includes force and pressure measurements for most configurations.

Off-highway machine mounting system isolation, especially the cab mounting system, significantly affects the operator comfort by providing damping to the harsh inputs and isolating the structure-borne energy from traveling into the cab. Mounting system isolation performance is decided not only by the isolation component, but also the mounting bracket structure, and should be treated as a system. This paper gives a review of how the mounting system isolates structural energy and the effect of the bracket structure stiffness to the mounting system isolation performance.

With the continuing improvements to thermoelectric (TE) materials and systems, their potential for both energy recovery and thermal management is increasingly apparent. Recent developments in materials and notably Skutterudites have allowed materials to be matched much more closely to the working temperatures of a light duty power-train. The choice of TE materials remains a substantial question in the design of a thermoelectric generator (TEG). While the quest for improvements in materials performance continues, the work reported in this paper is characterized by the decision to focus on the refinement of one class of TE materials: Skutterudites. In parallel, the engineering work on the integration of the TE materials into a heat exchanger could continue and be focused on the properties of this class of material. Skutterudites offer the combination of a high working temperature and a competitive electrical output (defined by ZT, the figure of merit).

This study applies the methodology developed for two earlier evaluations of diesel particulate controls to urban buses. Since these vehicles are used almost exclusively in urban areas where population is most dense, the analysis indicates the net benefits of control are very high.