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Li-ion batteries (LIBs) optimum performance and lifetime depend on temperature, with the commonly suggested operating temperature being in the range of 25 to 40 °C. It's also crucial to keep the temperature difference between battery cells below 5°C. Operation at different temperature ranges can adversely affect or degrade the performance and lifetime of LIBs. A battery thermal management system (BTMS) is essential for keeping the battery temperature within the optimum range. This paper aims to develop and analyze the BTMS for an electric heavy-duty truck. To achieve this aim, battery cells and modules are modelled in ANSYS Fluent software. Validation with experimental results and mesh sensitivity studies are also performed to increase confidence in simulation data. The model is then analyzed for a specific cooling systems to investigate its effect on battery thermal performance during the operation.

Due to the variability of real traffic conditions for vehicle testing, real-world vehicle performance estimation using simulation method become vital. Especially for heavy duty vehicles (e.g. 40 t trucks), which are used for international freight transport, real-world tests are difficult, complex and expensive. Vehicle simulations use mathematical methods or commercial software, which take given driving cycles as inputs. However, the road situations in real driving are different from the driving cycles, whose speed profiles are obtained under specific conditions. In this paper, a real-world vehicle performance estimation method using simulation was proposed, also it took traffic and real road situations into consideration, which made it possible to investigate the performance of vehicles operating on any roads and traffic conditions. The proposed approach is applicable to all kind of road vehicles, e.g. trucks, buses, etc. In the method, the real-road network includes road elevation.

This paper investigates the optimization of the aerodynamic design of a police car, BMW 5-series which is popular police force across the UK. A Bezier curve fitting approach is proposed as a tool to improve the existing design of the warning light cluster in order to reduce drag. A formal optimization technique based on Computational Fluid Dynamics (CFD) and moving least squares (MLS) is used to determine the control points for the approximated curve to cover the light-bar and streamline the shape of the roof. The results clearly show that improving the aerodynamic design of the roofs will offer an important opportunity for reducing the fuel consumption and emissions for police vehicles. The optimized police car has 30% less drag than the non-optimized counter-part.

Motion cueing algorithms can improve the perceived realism of a driving simulator, however, data on the effects on driver performance and simulator sickness remain scarce. Two novel motion cueing algorithms varying in concept and complexity were developed for a limited maneuvering workspace, hexapod/Stuart type motion platform. The RideCue algorithm uses a simple swing motion concept while OverTilt Track algorithm uses optimal pre-positioning to account for maneuver characteristics for coordinating tilt adjustments. An experiment was conducted on the US Army Tank Automotive Research, Development and Engineering Center (TARDEC) Ride Motion Simulator (RMS) platform comparing the two novel motion cueing algorithms to a pre-existing algorithm and a no-motion condition.

The tailpipe exhaust emissions were measured under real world urban driving conditions by using a EURO4 emissions compliant SI car equipped with an on-board heated FTIR for speciated gaseous emission measurements, a differential GPS for travel profiles, thermocouples for temperatures, and a MAX fuel meter for transient fuel consumption. Emissions species were measured at 0.5 Hz. The tests were designed to enable cold start to occur into congested traffic, typical of the situation of people living alongside congested roads into a large city. The cold start was monitored through temperature measurements of the TWC front and rear face temperatures and lubricating oil temperatures. The emissions are presented to the end of the cold start, defined when the downstream TWC face temperature is hotter than the front face which occurred at ∼350-400oC. Journeys at various times of the day were conducted to investigate traffic flow impacts on the cold start.

The tailpipe exhaust emissions were measured using a EURO4 emissions compliant SI car equipped with on-board measurement systems such as a FTIR system for gaseous emission, a differential GPS for velocity, altitude and position, thermal couples for temperatures, and a MAX fuel meter for transient fuel consumption. Various nitrogen species emissions (NO, NO2, NOx, NH3, HCN and N2O) were measured at 0.5 Hz. The tests were designed and employed using two real world driving cycles/routes representing a typical urban road network located in a densely populated area and main crowded road. Journeys at various times of the day were conducted to investigate traffic conditions impacts such as traffic and pedestrian lights, road congestion, grade and turning on emissions, engine thermal efficiency and fuel consumption. The time aligned vehicle moving parameters with Nitrogen pollutant emission data and fuel consumption enabled the micro-analysis of correlations between these parameters.

Direct use of straight vegetable oil based biofuels in diesel engines without trans-esterification can deliver more carbon reductions compared to its counterpart biodiesel. However, the use of high blends of straight vegetable oils especially used cooking oil based fuels in diesel engines needs to ensure compatible fuel economy with PD (Petroleum Diesel) and satisfactory operational performance. There are two ways to use high blends of SVO (Straight Vegetable Oil) in diesel engines: fixed blending ratio feeding to the engine and variable blending ratio feeding to the engine. This paper employed the latter using an on-board blending system-Bioltec system, which is capable of heating the vegetable oils and feeding the engine with neat PD or different blends of vegetable oils depending on engine load and temperature.

Aluminium alloys have been used extensively in the automotive industry to reduce the weight of a vehicle and improve fuel consumption which in turn leads to a reduction in engine emissions. The main aim of the current study is to replace the conventional cast iron rotor material with a lightweight alternative such as coated aluminium alloy. The main challenge has been to meet both the cost and functional demands of modern mass-produced automotive braking systems. A sensitivity analysis based on the Taguchi approach was carried out to investigate the effect of various parameters on the thermal performance of a typical candidate disc brake. Wrought aluminium disc brake rotors coated with alumina on the rubbing surfaces were determined to have the best potential for replacing the conventional cast iron rotor at reasonable cost. Optimisation of the structure was subsequently carried out using a genetic algorithm on the selected coated aluminium disc brake rotor.

A SI probe car, defined here as a normal commercial car equipped with GPS, in-vehicle FTIR tailpipe emission measurement and real time fuel consumption measurement systems, and temperature measurements, was used for measuring greenhouse gas emissions including CO2, N2O and CH4 under real world urban driving conditions. The vehicle used was a EURO4 emission compliant SI car. Two real world driving cycles/routes were designed and employed for the tests, which were located in a densely populated area and a busy major road representing a typical urban road network. Eight trips were conducted at morning rush hours, day time non-peak traffic periods and evening off peak time respectively. The aim is to investigate the impacts of traffic conditions such as road congestion, grade and turnings on fuel consumption, engine thermal efficiency and emissions.

The paper discusses the concept, design and final results from the ‘Ultra Boost for Economy’ collaborative project, which was part-funded by the Technology Strategy Board, the UK's innovation agency. The project comprised industry- and academia-wide expertise to demonstrate that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a modern, large-capacity naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles. In addition to achieving the torque curve of the Jaguar Land Rover naturally-aspirated 5.0 litre V8 engine (which included generating 25 bar BMEP at 1000 rpm), the main project target was to show that such a downsized engine could, in itself, provide a major proportion of a route towards a 35% reduction in vehicle tailpipe CO2 on the New European Drive Cycle, together with some vehicle-based modifications and the assumption of stop-start technology being used instead of hybridization.

This study uses on-board measurement systems to analyze emissions from a diesel engine vehicle during the cold start period. An in-vehicle FTIR (Fourier Transform Inferred) spectrometer and a Horiba on-board measurement system (OBS-1300) were installed on a EURO3 emission-compliant 1.8 TDCi diesel van, in order to measure the emissions. Both regulated and non-regulated emissions were measured, along with an analysis of the NO/NO₂ split. A VBOX GPS system was used to log coordinates and road speed for driving parameters and emission analysis. Thermal couples were installed along the exhaust system to measure the temperatures of exhaust gases during cold start. The real-time fuel consumption was measured. The study also looks at the influence of velocity on emissions of hydrocarbons (HCs) and NOx. The cold start period of an SI-engine-powered vehicle, was typically around 200 seconds in urban driving conditions.

The Swedish Biomimetics 3000's μMist® platform technology has been used to develop a radically new injection system. This prototype system, developed and characterized with support from Lotus, as part of Swedish Biomimetics 3000®'s V₂IO innovation accelerating model, delivers improved combustion efficiency through achieving exceptionally small droplets, at fuel rail pressures far less than conventional GDI systems and as low as PFI systems. The system gives the opportunity to prepare and deliver all of the fuel load for the engine while the intake valves are open and after the exhaust valves have closed, thereby offering the potential to use advanced charge scavenging techniques in PFI engines which have hitherto been restricted to direct-injection engines, and at a lower system cost than a GDI injection system.

This paper reports the results of a back-to-back comparison of the squeal and judder propensity of simple cast iron and siliconised carbon disk brake systems. A finite element simulation approach is used to predict the squeal propensity of the two systems based on the results of a complex eigenvalue analysis. These results which are validated by dynamometer noise tests carried out according to the SAE J2521 [1] standard procedure show that the siliconised carbon rotor is much less prone to squeal over the range of conditions considered. The combined experimental and numerical simulation approach is also applied to the problem of hot judder for the two rotors. The critical rotational speeds for hot spots to form are predicted to be an order of magnitude higher for the siliconised carbon rotor system. These results demonstrate the potential of the new carbon composite rotor material to reduce the occurrence of noise and vibration problems in automotive brakes.

This paper will present a method of estimating tyre friction force using an extended Kalman filter (EKF). A review of current and proposed methods for tyre force estimation from the literature will be given. The EKF developed will estimate vehicle motions and tyre forces as state estimates from a noisy measurement set. The tyre forces will be compared to those from a high order vehicle model with non-linear tyres, which is subjected to the same tests as the measured vehicle, in order to validate the estimated forces. The robustness of the estimator to noise and input errors will be tested. The ultimate aim of this work is to provide estimates of tyre forces to a controller such as ABS or TCS.

Most active control systems developed for passenger vehicles are developed as safety systems. These control systems usually focus on improving vehicle stability and safety while ignoring the effects on the vehicle driveability. While stability is the primary concern of these control systems the driveability of the vehicle is also an important consideration. An example of compromised driveability in a stability control system is brake based active yaw control. Brake based systems are very effective at stability control but can have a negative impact on the longitudinal dynamics of a vehicle. The objective of the vehicle control systems developed for the future will be to preserve vehicle driveability while ensuring the stability of the vehicle. In this work, active suspension and active drivelines are developed as stability control systems that have a minimal impact on the driveability of the vehicle.

Many active control systems are developed as safety systems for passenger vehicles. These control systems usually focus on improving vehicle stability and safety while ignoring the effects on the vehicle driveability. In the motorsport environment, increased stability is desirable but not if the driveability of the vehicle is heavily compromised. In this work, active suspension and active drivelines are examined to improve vehicle dynamics and enhance driveability while maintaining stability. The active control systems are developed as separate driveability and stability controls and tested individually then integrated to create a multi-objective control system to improve both driveability and stability. The controllers are tested with standard vehicle manoeuvres.

Modern engine developments result in very different gas pressure-temperature histories to those in RON/MON determination tests and strain the usefulness of those knock scales and their applicability in SI engine knock and HCCI autoignition onset models. In practice, autoignition times are complex functions of fuel chemistry and burning velocity (which affects pressure-temperature history), residual gas concentration and content of species such as NO. As a result, autoignition expressions prove inadequate for engine conditions straying far from those under which they were derived. The currently reported study was designed to separate some of these effects. Experimental pressure crank-angle histories were derived for an engine operated in skip-fire mode to eliminate residuals. The unburned temperature history was derived for each cycle and was used with a number of autoignition/knock models.

This paper proposes an advanced control strategy to improve vehicle handling and directional stability by integrating either Active Front Steering (AFS) or Active Rear Steering (ARS) with Variable Torque Distribution (VTD) control. Both AFS and ARS serve as the steerability controller and are designed to achieve the improved yaw rate tracking in low to mid-range lateral acceleration using Sliding Mode Control (SMC); while VTD is used as the stability controller and employs differential driving torque between left and right wheels on the same axle to produce a relatively large stabilizing yaw moment when the vehicle states (sideslip angle and its angular velocity) exceed the reference stable region defined in the phase plane. Based on these stand-alone subsystems, an integrated control scheme which coordinates the control actions of both AFS/ARS and VTD is proposed. The functional difference between AFS and ARS when integrated with VTD is explained physically.

In this paper a gearshift controller for twin clutch transmissions is developed. The controller incorporates the control of engine variables to achieve synchronization whilst the transfer of engine torque from clutch to clutch is managed by a clutch slip control. On top of this gearshift controller and as an extension to the basic control scheme a transmission output torque control is included as a means to directly influence shift character and add robustness to the control. The transmission output torque control also provides the foundation for an integrated torque management scheme of powertrain components. Simulation results for upshift and downshift are presented and discussed in the final chapter of this paper.

A non-linear contact analysis of a leading-trailing shoe drum brake, using the finite element method, is presented. The FE model accurately captures both the static and pseudo-dynamic behaviour at the friction interface. Flexible-to-flexible contact surfaces with elastic friction capabilities are used to determine the pressure distribution. Static contact conditions are established by initially pressing the shoes against the drum. This first load step is followed by a gradual increase of applied rotation to the drum in order to define the maximum reacted braking torque and pseudo-dynamic pressure distribution at the transition point between sticking and sliding motion. The method clearly illustrates the changes in contact force that take place as a function of the applied pressure, coefficient of friction and initial gap between lining and rotor. These changes in contact area are shown to influence the overall stability and therefore squeal propensity of the brake assembly.