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The performance of energy flow management strategies is essential for the success of hybrid electric vehicles (HEVs), which are considered amongst the most promising solutions for improving fuel economy as well as reducing exhaust emissions. The heavy duty HEVs engaged in cycles characterized by start-stop configuration has attracted widely interests, especially in off-road applications. In this paper, a fuzzy equivalent consumption minimization strategy (F-ECMS) is proposed as an intelligent real-time energy management solution for heavy duty HEVs. The online optimization problem is formulated as minimizing a cost function, in terms of weighted fuel power and electrical power. A fuzzy rule-based approach is applied on the weight tuning within the cost function, with respect to the variations of the battery state-of-charge (SOC) and elapsed time.

A control strategy has been designed for a city bus equipped with a pneumatic hybrid propulsion system. The control system design is based on the precise management of energy flows during both energy storage and regeneration. Energy recovered from the braking process is stored in the form of compressed air that is redeployed for engine start and to supplement the engine air supply during vehicle acceleration. Operation modes are changed dynamically and the energy distribution is controlled to realize three principal functions: Stop-Start, Boost and Regenerative Braking. A forward facing simulation model facilitates an analysis of the vehicle dynamic performance, engine transient response, fuel economy and energy usage.

Full hybrid electric vehicles are usually defined by their capability to drive in a fully electric mode, offering the advantage that they do not produce any emissions at the point of use. This is particularly important in built up areas, where localized emissions in the form of NOx and particulate matter may worsen health issues such as respiratory disease. However, high degrees of electrification also mean that waste heat from the internal combustion engine is often not available for heating the cabin and for maintaining the temperature of the powertrain and emissions control system. If not managed properly, this can result in increased fuel consumption, exhaust emissions, and reduced electric-only range at moderately high or low ambient temperatures negating many of the benefits of the electrification. This paper describes the development of a holistic, modular vehicle model designed for development of an integrated thermal energy management strategy.

Powertrain thermal encapsulation has the potential to improve fuel consumption and CO2 via heat retention. Heat retained within the powertrain after a period of engine-off, can increase the temperature of the next engine start hours after key-off. This in turn reduces inefficiencies associated with sub-optimal temperatures such as friction. The Ambient Temperature Correction Test was adopted in the current work which contains two World-wide harmonised Light duty Test Procedure (WLTP) cycles separated by a 9-hour soak period. A coupled 1D - 3D computational approach was used to capture heat retention characteristics and subsequent warm-up effects. A 1-D powertrain warm-up model was developed in GT-Suite to capture the thermal warm-up characteristics of the powertrain. The model included a temperature dependent friction model, the thermal-hydraulic characteristics of the cooling and lubrication circuits as well as parasitic losses associated with pumps.

This paper explores design methods for a vehicle handling dynamics state estimator based on a linear vehicle model. The state estimator is needed because there are some states of the vehicle that cannot be measured directly, such as sideslip velocity, and also some which are relatively expensive to measure, such as roll and yaw rates. Information about the vehicle states is essential for vehicle handling stability control and is also valuable in chassis design evaluation. The aim of this study is to compare the performance of a Kalman filter with that of a robust filter, under conditions which would be realistic and viable for a production vehicle. Both filters are thus designed and tested with reference to a higher order source model which incorporates nonlinear saturating tyre force characteristics. Also, both filters rely solely on accelerometer sensors, which are simulated with expected noise characteristics in terms of amplitude and spectra.

In the globalization of the automotive businesses, manufacturing companies and their suppliers are forced to distribute the various lifecycle phases in different geographical locations. Misunderstandings arising from the variety of personnel involved, each with different requirements, backgrounds, roles, cultures and skills for example can result in increased cost and development time. To enable collaborating companies to have a common platform for interaction, the COMPANION project at Loughborough University has been undertaken to develop a common model-based environment for manufacturing automotive engines. Through the use of this environment, the stakeholders will be able to “visualize” consistently the evolution of automated systems at every lifecycle stage i.e. requirements definition, specification, design, analysis, build, evaluation, maintenance, diagnostics and recycle.

Growing concerns about the environmental impact of road vehicles will lead to a reduction in the aerodynamic drag for all passenger cars. This includes Sport Utility Vehicles (SUVs) and light trucks which have relatively high drag coefficients and large frontal area. The wind tunnel remains the tool of choice for the vehicle aerodynamicist, but it is important that the benefits obtained in the wind tunnel reflect improvements to the vehicle on the road. Coastdown measurements obtained using a Land Rover Freelander, in various configurations, have been made to determine aerodynamic drag and these have been compared with wind tunnel data for the same vehicle. Repeatability of the coastdown data, the effects of drag variation near to zero yaw and asymmetry in the drag-yaw data on the results from coastdown testing are assessed. Alternative blockage corrections for the wind tunnel measurements are examined.

This paper reports on an investigation into the potential for a thermoelectric generator (TEG) to improve the fuel economy of a mild hybrid vehicle. A simulation model of a parallel hybrid vehicle equipped with a TEG in the exhaust system is presented. This model is made up by three sub-models: a parallel hybrid vehicle model, an exhaust model and a TEG model. The model is based on a quasi-static approach, which runs a fast and simple estimation of the fuel consumption and CO2 emissions. The model is validated against both experimental and published data. Using this model, the annual fuel saving, CO2 reduction and net present value (NPV) of the TEG’s life time fuel saving are all investigated. The model is also used as a flexible tool for analysis of the sensitivity of vehicle fuel consumption to the TEG design parameters. The analysis results give an effective basis for optimization of the TEG design.

The application of state-of-art thermoelectric generator (TEG) in automotive engine has potential to reduce more than 2% fuel consumption and hence the CO2 emissions. This figure is expected to be increased to 5%~10% in the near future when new thermoelectric material with higher properties is fabricated. However, in order to maximize the TEG output power, there are a few issues need to be considered in the design stage such as the number of modules, the connection of modules, the geometry of the thermoelectric module, the DC-DC converter circuit, the geometry of the heat exchanger especially the hot side heat exchanger etc. These issues can only be investigated via a proper TEG model. The authors introduced four ways of TEG modelling which in the increasing complexity order are MATLB function based model, MATLAB Simscape based Simulink model, GT-power TEG model and CFD STAR-CCM+ model. Both Simscape model and GT-Power model have intrinsic dynamic model performance.

PICASSOS was a UK government funded programme to improve the ability of automotive supply chains to develop complex software-intensive systems with high safety assurance and at an acceptable cost. This was executed by a consortium of three universities and five companies including an automotive OEM and suppliers. Three major elements of the PICASSOS project were: use of automated model based verification technology utilising formal methods; application of this technology in the context of ISO 26262; and evaluation to measure the impact of this approach to inform key management decisions on the costs, benefits and risks of applying this technology on live projects. The project spanned system level design and software development. This was achieved by using a unified model based process incorporating SysML at the system level and using Simulink and Stateflow auto-coded into C at the software level.

This paper surveys publications on automotive powertrain control, relating to modern GTDI (Gasoline Turbocharged Direct Injection) engines. The requirements for gasoline engines are optimising the airpath but future legislation suggests not only a finely controlled airpath but also some level of electrification. Fundamentals of controls modelling are revisited and advancements are highlighted. In particular, a modern GTDI airpath is presented based on basic building blocks (volumes, turbocharger, throttle, valves and variable cam timing or VCT) with an example of a system interaction, based on boost pressure and lambda control. Further, an advanced airpath could be considered with applications to downsizing and fuel economy. A further electrification step is reviewed which involves interactions with the airpath and requires a robust energy management strategy. Examples are taken of energy recovery and e-machine placement.

Electrification of aircraft is on track to be a future key design principal due to the increasing pressure on the aviation industry to significantly reduce harmful emissions by 2050 and the increased use of electrical equipment. This has led to an increased focus on the research and development of alternative power sources for aircraft, including fuel cells. These alternative power sources could either be used to provide propulsive power or as an Auxiliary Power Unit (APU). Previous studies have considered isolated design cases where a fuel cell system was tailored for their specific application. To accommodate for the large variation between aircraft, this study covers the design of an empirical model, which will be used to size a fuel cell system for any given aircraft based on basic design parameters. The model was constructed utilising aircraft categorisation, fuel cell sizing and balance of plant sub-models.

Piston compression rings are thin, incomplete circular structures which are subject to complex motions during a typical 4-stroke internal combustion engine cycle. Ring dynamics comprises its inertial motion relative to the piston, within the confine of its seating groove. There are also elastodynamic modes, such as the ring in-plane motions. A number of modes can be excited, dependent on the net applied force. The latter includes the ring tension and cylinder pressure loading, both of which act outwards on the ring and conform it to the cylinder bore. There is also the radial inward force as the result of ring-bore conjunctional pressure (i.e. contact force). Under transient conditions, the inward and outward forces do not equilibrate, resulting in the small inertial radial motion of the ring.

A number of market factors such as customer demand for improved connectivity and infotainment systems, automated driver assist systems and electrification of powertrain have driven an increase in the number of electrical systems within the cabin of automotive vehicles. These systems have limited operating temperature windows, therefore markets with high ambient temperatures and solar loading represent a significant challenge due to high cabin temperatures. Traditionally climatic facilities have been used replicate the conditions seen in these markets in order to understand the performance of the electrical systems. However such facilities have a number of limitations such as fixed solar arrays, secondary radiation from the walls and substantial operating costs limiting testing to envelope tests. Therefore the requirement for CAE based approach to more accurately represent the conditions seen in the real world is clear.

Previous research has highlighted that the formation of a sustained friction film, desired for stable and predictable friction performance, is highly dependent upon the region of the substrate (CMC) being examined. In attempt to improve the friction performance, notably bedding-in, research at LU has been developing coatings aimed at ensuring friction film development across the substrate. This paper focuses on the performance of one of these coating formulations, and examines the performance of this on a laboratory scale dynamometer. Subsequently, the coating has then been applied to a full size brake disc, as used on a prestige vehicle, for dynamometer testing at an industry scale for comparative purposes. On both lab and full scale samples the bedding performance shows improvements over the standard material, and at the full scale the coating indicates improved stability of subsequent friction performance through a modified AK Master test schedule.

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.

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.

Thermoelectric generator has very quickly become a hot research topic in the last five years because its broad application area and very attractive features such as no moving parts, low maintenance, variety of thermoelectric materials that total together cover a wide temperature range. The biggest disadvantage of the thermoelectric generator is its low conversion efficiency. So that when design and manufacture a thermoelectric generator for exhaust waste heat recovery from an automotive engine, the benefit of fuel consumption from applying a thermoelectric generator would be very sensitive to the weight, the dimensions, the cost and the practical conversion efficiency. Additionally, the exhaust gas conditions vary with the change of engine operating point. This creates a big challenge for the design of the hot side heat exchanger in terms of optimizing the electrical output of the thermoelectric generator during an engine transient cycle.

Reported in the current paper is a study into the cycle efficiency effects of utilising a complex valvetrain mechanism in order to generate variable in-cylinder charge motion and therefore alter the dilution tolerance of a Direct Injection Spark Ignition (DISI) engine. A Jaguar Land Rover Single Cylinder Research Engine (SCRE) was operated at a number of engine speeds and loads with the dilution fraction varied accordingly (excess air (lean), external Exhaust Gas Residuals (EGR) or some combination of both). For each engine speed, load and dilution fraction, the engine was operated with either both intake valves fully open - Dual Valve Actuation (DVA) - or one valve completely closed - Single Valve Actuation (SVA) mode. The engine was operated in DVA and SVA modes with EGR fractions up to 20% with the excess air dilution (Lambda) increased (to approximately 1.8) until combustion stability was duly compromised.

The management of surface water flows driven from the wind screen by the action of wipers and aerodynamic shear is a growing challenge for automotive manufacturers. Pressure to remove traditional vehicle features, such as A-Pillar steps for aesthetic, aeroacoustic and aerodynamic reasons increases the likelihood that surface water may be convected over the A-Pillar and onto the front side glass where it can compromise drivers’ vision. The ability to predict where and under which conditions the A-Pillar will be breached is important for making correct design decisions. The use of numerical simulation in this context is desirable, as experimental testing relies on the use of aerodynamics test properties which will not be fully representative, or late-stage prototypes, making it difficult and costly to correct issues. This paper provides an update on the ability of simulation to predict A-Pillar overflow, comparing physical and numerical results for a test vehicle.