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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.

Car manufacturers put large efforts into reducing wind noise to improve the comfort level of their cars. Each component of the vehicle is designed to meet its individual noise target to ensure the wind noise passenger comfort level inside the vehicle is met. Sunroof designs are tested to meet low-frequency buffeting (also known as boom) targets and broadband noise targets for the fully open sunroof with deflector and for the sunroof in vent position. Experimentally testing designs and making changes to meet these design targets typically involves high cost prototypes, expensive wind tunnel sessions, and potentially late design changes. To reduce the associated costs as well as development times, there is strong motivation for the use of a reliable numerical prediction capability early in the vehicle design process.

For most car manufacturers, wind noise from the greenhouse region has become the dominant high frequency noise contributor at highway speeds. Addressing this wind noise issue using experimental procedures involves high cost prototypes, expensive wind tunnel sessions, and potentially late design changes. To reduce the associated costs as well as development times, there is strong motivation for the use of a reliable numerical prediction capability early in the vehicle design process. Previously, a computational approach that couples an unsteady computational fluid dynamics solver (based on a Lattice Boltzmann method) to a Statistical Energy Analysis (SEA) solver had been validated for predicting the noise contribution from the side mirrors. This paper presents the use of this computational approach to predict the vehicle interior noise from the windshield wipers, so that different wiper placement options can be evaluated early in the design process before the surface is frozen.

The ability to assess noise transmitted through seals to cabin interiors early in the design process is very important for automotive manufacturers. When a seal design is inadequate, the noise transmitted can dominate the interior noise, making the wind noise performance of the vehicle unacceptable. This can cause launch delays, increasing costs and risking loss of sales. Designing seals using conventional experimental processes is challenging, since the location and strength of flow noise sources are not known when the seal design is planned. Making changes to the seal system after the tooling stage is expensive for manufacturers as tooling and redesign costs can be considerable. Deliberate overdesign by adding multiple layers of seals in a wide range of locations also can reduce profit by unnecessarily raising part and manufacturing costs.

A general purpose computer model has been developed for analyzing the thermal performance of thermofluid systems. The system thermal behaviour is governed by heat convection and conduction. The model represents a thermofluid system as a thermal network, consisting of several different fluid circuits which are separated by solid walls. The solid walls are represented by hexahedral elements with lumped heat capacitance. The model has the capability to set up and link an equivalent thermal network from input data, using two types of junctions: wall-to-wall and fluid-to-wall. The flow calculations are based on the one-dimensional incompressible flow equation and the heat transfer calculations are based on either forced or natural heat convection for internal and external flows. The heat convection formulae used in the model are in the non-dimensional form which simplifies the program structure.

An on line method for verification of chassis dynamometer operation uses a neural network. During the testing of a vehicle, it is assumed that after a warm up period the parasitic losses remain stable. There is normally no provision for verification of correct dynamometer operation while the test is running. This technique will detect if a component wears or fails during the testing of a vehicle and thus avoid testing under erroneous conditions. A Learning Vector Quantization (LVQ) neural network is trained to recognise poor dynamometer operation in order to signal a fault condition to the operator.

Engines equipped with pressure charging systems are more prone to knock partly due the increased intake temperature. Meanwhile, turbocharged engines when operating at high engine speeds and loads cannot fully utilize the exhaust energy as the wastegate is opened to prevent overboost. The turboexpansion concept thus is conceived to reduce the intake temperature by utilizing some otherwise unexploited exhaust energy. This concept can be applied to any turbocharged engines equipped with both a compressor and a turbine-like expander on the intake loop. The turbocharging system is designed to achieve maximum utilization of the exhaust energy, from which the intake charge is over-boosted. After the intercooler, the turbine-like expander expands the over-compressed intake charge to the required plenum pressure and reduces its temperature whilst recovering some energy through the connection to the crankshaft.

Vehicle efficiency and range, along with the DC charging speed, are deemed as the most important criteria for an electric vehicle currently. The electric vehicle energy consumption is impacted by the change in temperature along with the driving style and average speed of a customer, all other factors being constant. Hence understanding the patterns and impact of different aspects of an EV range & charging speed is crucial in delivering an electric vehicle with robust efficiency across all weather conditions. In this paper we have analysed vehicle parameters of global Jaguar I-PACE customer data. We present and analyse the collated big data of around 50,000+ unique vehicles with a data aggregate of well over 482 million km. In moderate ambient conditions the analysis indicated a good correlation with 50th to 75th percentile drivers’ energy consumption to the EPA label figure.

Complexity of electronics and embedded software systems in automobiles has been increasing over the years. This necessitates the need for an effective and exhaustive development and validation process in order to deliver fault free vehicles at reduced time to market. Model-based Product Engineering (MBPE) is a new process for development and validation of embedded control software. The process is generic and defines the engineering activities to plan and assess the progress and quality of the software developed for automotive applications. The MBPE process is comprised of six levels (one design level and five verification and validation levels) ranging from the vehicle requirements phase to the start of production. The process describes the work products to be delivered during the course of product development and also aligns the delivery plan to overall vehicle development milestones.

This paper describes the development and validation of a refined combustion model for turbulent flame propagation in SI engines. In this model the original differential equation of flame front entrainment remains, but a new difference equation of burning rate is introduced to replace the original differential equation. The model fully embodies the Tennekes-Chomiak mechanism of premixed turbulent combustion, presenting a flame thinner than the original model. A spark ignition model is also suggested. The model treats the electrical spark ignition as a diffusion wave to calculate the entrainment enhancement by the spark ignition. The simple formula of the initial flame propagation has been validated by measured results. Incorporated with this spark ignition model, the three-stage model of premixed turbulent flame velocity, published earlier by the authors, is used in the combustion model.

The objective of the Project is to develop an optimized lead-acid battery solution for HEVs based on a novel, individual, spirally wound valve-regulated lead-acid 2V cell optimized for HEV use and low variability. This cell will be used as a building block for the development of a complete battery pack that is managed at the cell level. Following bench testing, this battery pack will be thoroughly evaluated by substituting it for the NiMH pack in a Honda Insight. The paper covers the first half of the 3-year project and will describe work carried out in the following areas: Development of cell and battery testing facilities and identification of mechanisms causing cell lifetime scatter. The design and development of the prototype double-ended cell. The development of the battery pack specification and pack design. The development of the battery management system. The paper will also give details of the test results obtained on the demonstration vehicle with its original NiMH battery.

This paper discusses the use of SLIO CAN technology for low speed (<125 Kbit/s) body control system. The architecture of SLIO as well as its benefits and shortcomings are explained and illustrated. A body control system utilising the SLIO CAN technology has been build to investigate the feasibility of its implementation. The flexibility in adding enhancement and fault tolerance feature to the system is also addressed. The prior knowledge of CAN Specification 2.0 is assumed[1].

With the introduction of vehicular digitization and automation, there has been significant growth in the number of Electronic Control Units (ECUs) inside vehicles, followed by the broader use of Advanced Driver Assistance Systems (ADAS) and Automated Driving Systems (ADSs). The growth of the number of ECUs has also significantly increased the number of user interfaces. To conduct safe driving, in addition to those related to the real-time control of the vehicle, a driver also needs to be able to digest information effectively and efficiently from various ECUs via the Human-Machine Interface (HMI). To evaluate the safety of ADS, including its interactions with system users, some work has suggested that they will need to be driven for over 11 billion miles. However, the number of test miles driven is not a meaningful metric for judging safety. Instead, the types of scenarios encountered by the driver-vehicle interactions during testing are critically important.

Hardware-in-the-loop (HIL) simulations have long been used to test electronic control units (ECUs) and software in car manufacturers. It provides an effective platform to the rapid development process of the ECU control algorithms and accommodates the added complexity of the plant under control. Accurate Model based HIL simulation (AMHIL) is considered as a most efficient and cost effective way for exploration of new designs and development of new products, particularly in calibration and parameterization of vehicle stability controllers. The work presented in the paper is to develop a mathematical model of a windscreen wiper system for the purpose of conducting HIL vehicle test and eventually to replace the real component with the model for cost cutting and improved test efficiency. The model is developed based on the electro-mechanical engineering principles.

The advent of 3D displays offers Human-Machine Interface (HMI) designers and engineers new opportunities to shape the user's experience of information within the vehicle. However, the application of 3D displays to the in-vehicle environment introduces a number of new parameters that must be carefully considered in order to optimise the user experience. In addition, there is potential for 3D displays to increase driver inattention, either through diverting the driver's attention away from the road or by increasing the time taken to assimilate information. Manufacturers must therefore take great care in establishing the ‘do’s and ‘don’t's of 3D interface design for the automotive context, providing a sound basis upon which HMI designers can innovate. This paper describes the approach and findings of a three-part investigation into the use of 3D displays in the instrument cluster of a road car, the overall aim of which was to define the boundaries of the 3D HMI design space.

The field of vision of the driver during wet road conditions is essential for safety at all times. Additionally, the safe use of the increasing number of sensors integrated in modern cars for autonomous driving and intelligent driver assistant systems has to be ensured even under challenging weather conditions. To fulfil these requirements during the development process of new cars, experimental and numerical investigations of vehicle soiling are performed. This paper presents the surface contamination of self- and foreign-soiling tested in the wind tunnel. For these type of tests, the fluorescence method is state-of-the-art and widely used for visualizing critical areas. In the last years, the importance of parameters like the contact angle have been identified when designing the experimental setup. In addition, new visualization techniques have been introduced.

The Controller Area Network (CAN) has seen enormous success in automotive body and powertrain control systems. However, there is a change in emphasis arising in the industry in which CAN is seen as too powerful and expensive for simple digital body control applications, but not robust or fast enough for more safety critical applications such as the envisaged Drive-by-Wire systems of future passenger cars. The emerging protocols Local Interconnect Network (LIN), the Time Triggered Protocols (TTP/A, TTP/C), Time Triggered CAN (TTC) and Byteflight are examined in terms of their application and likelihood for future success. The paper is concluded with comments concerning a newly announced protocol known as FlexRay.

The Controller Area Network (CAN) has seen enormous success in automotive body and powertrain control systems, as well as industrial automation systems using higher layer protocols such as CANopen and DeviceNet. Now, the CAN standard ISO11898 is being extended to Time Triggered CAN (TTCAN) to address the safety critical needs of first generation drive-by-wire systems. However, their successful development depends upon the availability of silicon and software support, and appropriate development & analysis tools. Warwick Control Technologies and the University of Warwick are tasked with prototyping a TTCAN analyser within the European Union Media+ project Silicon Systems for Automotive Electronics (SSAE) consortium, and with funding from the British Department of Trade and Industry (DTI). This paper briefly outlines the current status of both CAN & TTCAN technology and describes the requirements of a TTCAN analyser over that of a traditional CAN analyser.

Flash-boiling of sprays may occur when a superheated liquid is discharged into an ambient environment with lower pressure than its saturation pressure. Such conditions normally exist in direct-injection spark-ignition engines operating at low in-cylinder pressures and/or high fuel temperatures. The addition of novel high volatile additives/fuels may also promote flash-boiling. Fuel flashing plays a significant role in mixture formation by promoting faster breakup and higher fuel evaporation rates compared to non-flashing conditions. Therefore, fundamental understanding of the characteristics of flashing sprays is necessary for the development of more efficient mixture formation. The present computational work focuses on modelling flash-boiling of n-Pentane and iso-Octane sprays using a Lagrangian particle tracking technique.

For the automotive industry, the quality and level of the wind noise contribution has a growing importance and therefore should be addressed as early as possible in the development process. Each component of the vehicle is designed to meet its individual noise target to ensure the wind noise passenger comfort level inside the vehicle is met. Sunroof broadband noise is generated by the turbulent flow developed over the roof opening. A strong shear layer and vortices impacting on the trailing edge of the sunroof are typical mechanisms related to the noise production. Sunroof designs are tested to meet broadband noise targets. Experimentally testing designs and making changes to meet these design targets typically involves high cost prototypes, expensive wind tunnel sessions and potentially late design changes.