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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).

Model-based calibration (MBC) is a systematic method to calibrate an engine control unit (ECU) system. Due to the working principle of MBC, it is only being used for steady-state systems (time independent models). This limits the use of MBC; because an ECU contains statistical and dynamical systems. Due to the limitations of MBC, dynamical systems require manual tuning which may be time-consuming. With the increasing popularity in hybrid and electrical vehicle systems, most of them rely on dynamical systems. Therefore, MBC is about to be superseded by manual parameterization methods. Remarkably, MBC is not limited to the steady state systems. It can be achieved by separating the time factor of a system and extracting the statistical data from a time series measurement. Typically, MBC model is conceived as the representation of a system plant (i.e.: air path, fuel path, mean value engine model). As a matter of fact, MBC model is not limited to identification of system plant.

Panel Discussions held at the SAE World Congress in both 2013 and 2014 observed that a shortage of good quality engineering talent formed a chronic and major challenge. (“Good quality” refers to applicants that would be shortlisted for interview.) While doubts have been expressed in some quarters, the shortage is confirmed by automotive sector employers and the Panel's view was that it was symptomatic of a range of issues, all of which have some bearing on the future of the profession. Initiatives to improve recruitment and retention have had varying degrees of success. Efforts need to be intensified in primary schools where negative perceptions develop and deepen. Schemes like AWIM that operate on a large scale and are designed to supplement school curricula should operate at an international level. Universities represent the entry point into the engineering profession and their role in the recruitment process as well as education and training is crucial.

A full calibration exercise of a diesel engine air path can take months to complete (depending on the number of variables). Model-based calibration approach can speed up the calibration process significantly. This paper discusses the overall calibration process of the air-path of the Cat® C7.1 engine using statistical machine learning tool. The standard Cat® C7.1 engine's twin-stage turbocharger was replaced by a VTG (Variable Turbine Geometry) as part of an evaluation of a novel air system. The changes made to the air-path system required a recalculation of the air path's boost set point and desired EGR set point maps. Statistical learning processes provided a firm basis to model and optimize the air path set point maps and allowed a healthy balance to be struck between the resources required for the exercise and the resulting data quality.

There has probably never been such a demand for professionally qualified engineers, and yet both the number and diversity of people entering the profession continue to decline. Worldwide, there are very many initiatives - some generally encouraging interest in the profession, and others targeting specific audiences. The reports speak of local success, but the overall picture remains discouraging. In this paper we focus on the “pipeline” from primary education through to the transition from graduate engineer into an experienced member of engineering staff. We have based the discussion on both the presentations and comments made during a panel discussion held at the 2013 SAE International Congress. The paper is intended as a summary of the points raised during that discussion and, we hope proves to be starting point for further investigation and analysis. Of particular note is the sheer diversity of initiatives, and the pressing need for role models and mentoring.

Recent work on thermo-electric (TE) systems has highlighted the need for refined heat transfer design as well as the long standing need for improved materials performance. Recent work on heat transfer for TE systems has shown that enhanced heat transfer is needed over and above what would normally be seen in a vehicle exhaust system. In particular a better understanding of flow development and boundary layer behaviour is needed to support new design proposals. In the meantime, recent work in TE materials suggests that with the use of skutterudites significant performance benefits can accrue over existing materials. The current generation of TE materials have non-dimensional thermoelectric figure of merit (ZT) values of around 1. Skutterudites have been demonstrated to have ZT values of about 1.4 and can maintain these values over a wider temperature range than do existing materials through the engineering of the TE device.

The notion of open source systems has been well established in systems software and typified by the development of the Linux operating system. An open source community is a community of interest that makes use of software tools in research and development. Their ongoing development is part of the free flow of ideas on which the community. The motivation for the work reported in this paper is to provide the research community in engine controls with a ready access to a complete engine management solution and the component parts. The work described in this paper extends open source principles to engine control with a portable spark ignition (SI) control strategy assembled using Simulink. The underlying low level drivers are written in C and designed for portability. A calibration tool is written in C and works over a controller area network (CAN) link to the engine control unit (ECU). The ECU hardware is based on the Infineon Tricore microcontroller.

The recent development of diesel engine fuel injection systems has been dominated by how to manage the degrees of freedom that common rail multi-pulse systems now offer. A number of production engines already use four injection events while in research, work based on up to eight injection events has been reported. It is the degrees of freedom that lead to a novel experimental requirements. There is a potentially complex experimental program needed to simply understand how injection parameters influence the combustion process in steady state. Combustion behavior is not a continuum and as both injection and EGR rates are adjusted, distinct combustion modes emerge. Conventional calibration processes are severely challenged in the face of large number of degrees of freedom and as a consequence new development approaches are needed.

The promise of thermo-electric (TE) technology in vehicles is a low maintenance solid state device for power generation. The Thermo-Electric Generator (TEG) will be located in the exhaust system and will make use of an energy flow between the warmer exhaust gas and the external environment. The potential to make use of an otherwise wasted flow of energy means that the overall system efficiency can be improved substantially. One of the barriers to a successful application of the technology is the device efficiency. The TE properties of even the most advanced materials are still not sufficient for a practical, cost effective device. However the rate of development is such that practical devices are likely to be available within the next fifteen years. In a previous paper [ 1 ], the potential for such a device was shown through an integrated vehicle simulation and TEG model.

Hybrid solutions to propulsion system requirements permit novel solutions to load cycle requirements. By distributing the load between two devices whose efficiency characteristics are complementary, the overall efficiency can be tailored by blending the load contribution. The potential of such a combination is further enhanced if the combination of the devices results in a more complete conversion of fuel than a single device operating alone. In this paper we present a conceptual design for a powerplant made up of a fuel preparation sub-system and a diesel engine. The sub-system is made up of a reformer and solid oxide fuel cell stack that provides a stream of gaseous fuel and air to the engine, as well as producing electrical power. In this configuration the system is essentially an actuator that is controlled through the imposed electrical load. The fuel cell based pre-treatment device has a higher inherent efficiency than the engine.

This paper presents the conclusions of a study into the way the Formula SAE project works in the UK academic sector. The motivation for the work arose during the introduction of the project at the University of Sussex when we needed to evaluate the cost effectiveness of the project as part of the engineering curriculum. The traditional view of FSAE in the UK was that it proved a valuable recruitment tool and when only a few universities offered the project to students this was clearly the case. However now that the project is more widely adopted and where smaller Departments are now supporting the project, there is a need to look more closely at the effectiveness of the project. Identification of the factors that make a successful entry has also helped in an evaluation of the resource requirements. The general conclusion from the work is that Departments must work to extract the benefits of the project through curriculum planning.

At Sussex our attempts to introduce Formula SAE were initially slow and the results disappointing. At the same time we were developing and introducing modules in our engineering programmes that were entirely project-based, and in one case, included only e-learning, (with no lectures) after an introductory briefing. Formula SAE made faltering progress whilst it remained a voluntary activity. Support of a voluntary group by means of individually assessed projects at both undergraduate and masters level simply led to a series of unconnected technologies, although they were to prove of value later. Project-based activity in engineering had three distinctive characteristics which were to form our approach to Formula SAE: the need for a strong team ethos from the start of the project; an acceptance of the importance of process, and in particular project planning; and strong communication.

A promising technology for active safety is “X-by-Wire”, where mechanical and electromechanical components are replaced by electronic functions. One of the reasons for this is to have more than the driver input in the command chain, and also include some degree of intervention by the control system in case the driver behaviour is likely to put the car at risk. The adoption of a small number of computing nodes is a clear trend in vehicle design. A wide range of functions that are now distributed in the form of separate modules will instead be integrated. This approach will overcome the physical constraints of electrical and mechanical components and the costs of many separate electronic modules with their own power supplies.

The Formula SAE competition (known as Formula Student in the UK) is well established and continues to be highly popular with engineering students. The annual United Kingdom competition bears witness to this enthusiasm with a strong turnout of a total of 84 teams, including 41 teams from the United Kingdom and 21 other nations represented in 2004. In 2004 some countries, including Japan, Australia and South Korea participated for the first time. There are, for a university, significant implications of resource costs when running the Formula SAE project, mainly financial and time. Time costs in particular are acute with supervision time from university faculty groups and technicians (this latter being particularly intense). This investment needs justification in the light of other demands.

Fuel cell technology continues to attract a great deal of interest as an alternative power source to the internal combustion engine. Substantial technical progress has been made over the years and the appearance of the first vehicles offered in the commercial market mark a significant step. However, broad application and the eventual success of fuel cell technology in vehicles remain elusive. In this second edition of Fuel Cell Technology for Vehicles, the latest research and technological advances in fuel cell technology are examined in a comprehensive collection of 48 SAE Technical Papers, several articles from the Journal of Power Sources, plus bibliographical data for nearly 200 documents published by SAE and other leading sources.

Increasingly tighter automotive emissions legislation not only demands advanced catalyst control for super ultra low emission vehicle (SULEV) requirements, but also a close monitoring of catalyst performance. In the present paper, a control-oriented model is proposed that uses a library of four nonlinear (NARMAX) dynamic models to predict the three-way catalyst (TWC) transient response. Each nonlinear model is optimised for use under a certain operating region. In order to identify the current operating region and select the appropriate local model for prediction, the rate of change of stored oxygen is monitored. A simplified chemical model, which is based on the dynamics of the fundamental chemical reactions that occur inside the catalyst, is used for this purpose. The developed catalyst model only requires knowledge of the upstream/downstream air-fuel ratio (AFR) and it could form the basis of an on-board catalyst monitoring and control system.

Fuel cell power for cars appears to be the most promising alternative power-train technology. It is not alone in being touted as a likely successor to the diesel or gasoline fuelled internal combustion engine (ICE). What makes a significant difference is the extent of support that has been recently offered by vehicle manufacturers from their own research and development budgets. In spite of investment and strong interest to get fuel cell powered vehicles into the market there remain a series of question marks over the concept of fuel cell powered cars. Some concern technology - can fuel cells deliver an efficiency which meets performance criteria? Others are social and concerned with the acceptability of the car to the buying public and its green credentials. While the technical issues are the subject of a number of development programs, the other issues lie in the domain of marketing and the forming of public opinion.

The information needs of engines have increased dramatically over recent years. In order to achieve the levels of performance and endurance that are now required in the marketplace, engine operation increasingly employs sophisticated control with closed-loop operation of various functions. This control trend will continue as performance expectations increase, calibration times reduce and systems become more complex and dependent on a variety of sensors. Available and emerging technologies offer a range of solutions for sensor systems but success in any particular application is often difficult to analyze. This makes the prediction of future trends more difficult. This paper looks back at some recent developments and forward to the next few years. In addition to the sensors required, some consideration is also given to control systems, which have increased dramatically in sophistication.

Diesel engine control has already become complex, and in order to meet future emissions standards (such as Euro 4) it is likely to be the control system that will provide the needed performance increment. Common rail fuel injection offers yet more degrees of freedom which will need to be exploited as new emissions standards emerge. Whatever the emissions standards, there is a need to reduce risk at the earliest stages in the development of the powertrain. This will involve early and extensive simulation of the powertrain including its control system, sensors and actuators. What is the best way to achieve this using current tools? The result lies in a combination of a phenomenological model of the engine and a flexible controls environment. To illustrate the principles of developing prototype control systems, we will use the example of the CPower environment, which is a combination of a detailed engine simulation code (GT-Power) and the Simulink simulation environment.

In the context of engine control the strategy is a statement of the control functions. Modern strategies are generally map based with a resolution corresponding to single cylinder events. However, future needs point to high speed control based on sensors which can observe cylinder events. Such sensors working with actuators such as gasoline and diesel fuel injection can act to minimise variations between cylinders and more closely control combustion conditions. A high speed strategy is a functional description of control which includes such high speed functions One strategy can be solved using different control structures and with different sensor types. A cascaded control scheme for example would allow high speed cylinder level controls to be fed by slower controllers able to take a longer term view. Such a cascaded scheme is a framework which allows high level diagnosis and control objectives to be realised within a common framework.