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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 investigates the surface pressures found on the sides of a Davis model under steady state conditions and during yawed oscillations at a reduced frequency which would generally be assumed to give a quasi-static response. The surface pressures are used to investigate the flow field and integrated to infer aerodynamic loads. The results show hysteresis in the oscillating model's results, most strongly in the A-pillar flows. The changes to the oscillating model's flow field reduces the intensity of the surface pressures around the rear pillars, reduce the strength and extent of the A-pillar vortex and cause the surface pressures to couple with the oscillating motion. This work shows the flows around the front of a vehicle may be more important to a vehicle's unsteady aerodynamics than is generally accepted and also leads to the conclusions that the reduced frequency parameter may not fully describe the onset unsteadiness.

The importance of new technologies to improve the performance and fuel economy of internal combustion engines is now widely recognized and is essential to achieve CO₂ emissions targets and energy security. Increased hybridization, combustion improvements, friction reduction and ancillary developments are all playing an important part in achieving these goals. Turbocharging technology is established in the diesel engine field and will become more prominent as gasoline engine downsizing is more widely introduced to achieve significant fuel economy improvements. The work presented here introduces, for the first time, a new technology that applies conventional turbomachinery hardware to depressurize the exhaust system of almost any internal combustion engine by novel routing of the exhaust gases. The exhaust stroke of the piston is exposed to this low pressure leading to reduced or even reversed pumping losses, offering ≻5% increased engine torque and up to 5% reduced fuel consumption.

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.

A large contribution to the aerodynamic drag of a vehicle is the loss of pressure in the wake region, especially on square-back configurations. Wake pressure recovery can be achieved by a variety of physical shape changes, but with vehicle shapes becoming ever more aerodynamically efficient research into active technologies for flow manipulation is becoming more prominent. The aim of the current paper is to generate an understanding of how an optimized roof trailing edge, in the form of a chamfer, can reduce wake size, increase base pressures and reduce drag. A comprehensive study using PIV (Particle Image Velocimetry), balance measurements and static pressure measurements was performed in order to investigate the flow and wake structure behind a simplified car model. Significant reductions in C d are demonstrated and directly related to the measured base and slant pressures.

New European emissions legislation (Euro5) specifies a limit for Particle Number (PN) emissions and therefore drives measurement of PN during vehicle development and homologation. Concurrently, the use of biofuel is increasing in the marketplace, and Euro5 specifies that reference fuel must contain a bio-derived portion. Work was carried out to test the effect of fuels containing different levels of Fatty Acid Methyl Ester (FAME) on particle number, size, mass and composition. Measurements were conducted with a Cambustion Differential Mobility Spectrometer (DMS) to time-resolve sub-micron particles (5-1000nm), and a Horiba Solid Particle Counting System (SPCS) providing PN data from a Euro5-compliant measurement system. To ensure the findings are relevant to the modern automotive business, testing was carried out on a Euro4 compliant passenger car fitted with a high-pressure common-rail diesel engine and using standard homologation procedures.

The dynamics of automotive differentials have been studied extensively to improve their efficiency and additionally, in recent years, generated noise and vibration. Various mathematical models have been proposed to describe the contact/impact of gear teeth pairs. However, the influence of vehicular cruising speed on the resisting torque has not been considered in sufficient detail. This can lead to unrealistic predictions with regards to loss of contact of teeth pair, a phenomenon which leads to NVH issues. The current work presents a torsional model of a hypoid gear pair. The resisting torque is a function of the traction force and aerodynamic drag, whilst the vehicle is cruising at nominally constant speed. The pinion input torque is derived through assumed instantaneous equilibrium conditions. In this approach, realistic excitation capturing the vehicle's driving conditions is imposed on the dynamics of the hypoid gear pair.

Anticipating the need to improve the level of comfort for passengers in future aircraft designs, a study on the cost of providing more space for economy class seating has been conducted. Using an existing aircraft design (B777) as the baseline and British Airways published accounts it was shown that only about three extra economy ticket sales would be necessary to offset the operating cost increase associated with the larger fuselage. Franchising and carriage of cargo in the extra space was also investigated but shown to be uneconomic. The effect of aircraft size was studied by applying the analysis to a larger (MD12) and smaller (B757) aircraft. These investigations showed that provision of extra space is more advantageous for the larger aircraft but still remains economic for the smaller type. The method provides the basis for more detailed analysis in future studies.

Particle Image Velocimetry has developed over the last decade into a relatively mature flow-field measurement technique, capable of providing insight into time averaged and instantaneous flows that in the past have not been readily accessible. The application of the method in the measurement and analysis of flows around road vehicles has so far been limited to a relatively small number of specialist applications, but its use is expanding. This paper reviews the modern digital PIV technique placing emphasis on the important considerations required to obtain reliable and accurate data. This includes comments on each aspect of the PIV process, including initial setup and image acquisition, processing, validation and analysis. A number of automotive case studies are presented covering different aspects of the method, including a diffuser exit flow, edge radius optimization, ‘A’ pillar flow and aerial wake flows.

In this paper the effect of in-cylinder crevices formed by the piston cylinder clearance, above the first ring, and the spark plug cavity, on the entrapment of unburned fuel air mixture during the late compression, expansion and exhaust phases of a spark ignition engine cycle, have been simulated using the Computational Fluid Dynamic (CFD) code KIVA II. Two methods of fuelling the engine have been considered, the first involving the carburetion of a homogeneous fuel air mixture, and the second an attempt to simulate the effects of manifold injection of fuel droplets into the cylinder. The simulation is operative over the whole four stroke engine cycle, and shows the efflux of trapped hydrocarbon from crevices during the late expansion and exhaust phases of the engine cycle.

Turbochargers are progressively used in modern automotive engines to enhance engine performance and reduce energy loss and adverse emissions. Use of turbochargers along with other modern technologies has enabled development of significantly downsized internal combustion engines. However, turbochargers are major sources of acoustic emissions in modern automobiles. Their acoustics has a distinctive signature, originating from fluid-structure interactions. The bearing systems of turbochargers also constitute an important noise source. In this case, the acoustic emissions can mainly be attributed to hydrodynamic pressure fluctuations of the lubricant film. The developed analytical model determines the lubricant pressure distribution in the floating journal bearings used mainly in the modern turbocharges. This allows for an estimation of acoustic emissions.

Stringent IC engine PM emission regulation requires development of future filter substrate materials to achieve high filtration efficiency, low filter pressure drop, low cost and highly durable solutions. Monolithic wall flow filters perform well as they achieve high filtration efficiency due to the formation of the PM cake structure while maintaining low substrate face velocities due to the large filtration area. Within the process industry, Micropore™ slotted metallic membrane filters offer both large surface areas and low filter pressure drops while maintaining the durability of metal substrates. The pore structure and pore arrangement can be readily tailored to suit specific applications. This paper characterizes a 300 μm thickness Micropore™ metallic membrane with slots of 10 μm by 400 μm in size in the context of application as an engine exhaust particulate filter. The investigation was based on single layer of Micropore™ slotted metallic membrane with size of 52 mm in diameter.

Crankcase emissions are a complex mixture of combustion products and, specifically Particulate Matter (PM) from lubricant oil. Crankcase emissions contribute substantially to the particle mass and particle number (PN) emitted from an internal combustion engine. Environmental legislation demands that the combustion and crankcase emissions are either combined to give a total measurement or the crankcase gases are re-circulated back into the engine, both strategies require particle filtration. There is a lack of understanding regarding the physical processes that generate crankcase emissions of lubricant oil, specifically how the bulk lubricant oil is atomised into droplets. In this paper the crankcase of a motored compression ignition engine, has been optically accessed to visualise the lubricant oil distribution. The oil distribution was analysed in detail using high speed laser diagnostics, at engine speeds up to 2000 rpm and oil temperatures of 90°C.

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.

Recent changes to the rules regarding aerodynamics within Formula SAE, combined with faster circuits at the European FSAE events, have made the implementation of aerodynamic devices, to add down-force, a more relevant topic. As with any race series it is essential that a detailed analysis is completed to establish the costs and benefits of including an aerodynamic package on the vehicle. The aim of the work reported here was to create a methodology that would fully evaluate all aspects of the package and conclude with an estimate of the likely gain in points at a typical FSAE event. The paper limits the analysis to a front and rear wing combination, but the approach taken can be applied to more complex aerodynamic packages.

Coastdown testing is a proven method for determining the drag coefficients for road cars whilst the vehicle is in its normal operating environment. An accurate method of achieving this has been successfully developed at Loughborough University. This paper describes the adaptation and application of these techniques to the special case of a contemporary Formula One racing car. The work was undertaken in conjunction with the Benetton Formula One racing team. The paper outlines the development and application of a suitable mathematical model for this particular type of vehicle. The model includes the aerodynamic, tyre, drivetrain and the un-driven wheel drags and accounts for the change in aerodynamic drag due to ambient wind and changes in vehicle ride height during the coastdown. The test and analysis methods are described.

This paper determines the number of in-flight icing accidents and incidents, which can be attributed to tailplane icing. The paper also shows that pneumatic de-icing boots suffer from significant numbers of in-flight failures and poor levels of unscheduled maintenance. The possibility of retrofitting an improved ice protection system to the tailplane of a generic turboprop powered commuter aircraft is then investigated. A range of alternative ice protection systems are evaluated and the effects of retrofitting an Electro-Expulsive De-Icing System (EEDS) are evaluated in terms of changes to aircraft performance, variable direct operating and delay costs.

An experiment is described in which students from two universities, one in the UK and one in the USA, worked together in multidisciplinary teams on aircraft design projects to satisfy the “capstone” design course requirements in their respective degree programs. Aeronautical, Mechanical, Industrial, and Systems Engineering students from Virginia Tech and Loughborough University were placed on teams to work on two different airplane designs. The paper describes the evolution of this educational collaboration and the organization of the experiment. It also reviews the program ’s successes and its problems. Recommendations are made for continuation of the program and to guide others who might be interested in pursuing a similar experiment.

The aim of this paper is to compile the state of the art of engine control and develop scenarios for improvements in a number of applications of engine control where the pace of technology change is at its most marked. The first application is control of downsized engines with enhancement of combustion using direct injection, variable valve actuation and turbo charging. The second application is electrification of the powertrain with its impact on engine control. Various architectures are explored such as micro, mild, full hybrid and range extenders. The third application is exhaust gas after-treatment, with a focus on the trade-off between engine and after-treatment control. The fourth application is implementation of powertrain control systems, hardware, software, methods, and tools. The paper summarizes several examples where the performance depends on the availability of control systems for automotive applications.

A 2-stroke combustion cycle has higher power output densities compared to a 4-stroke cycle counterpart. The modern down-sized 4-stroke engine design can greatly benefit from this attribute of the 2-stroke cycle. By using appropriate variable valvetrain, boosting, and direct fuel injection systems, both cycles can be feasibly implemented on the same engine platform. In this research study, two valve strategies for achieving a two-stroke cycle in a four-stroke engine have been studied. The first strategy is based on balanced compression and expansion strokes, while the gas exchange is done through two different strokes. The second approach is a novel 2-stroke combustion strategy - here referred to as 2-stroke Miller - which maintains the expansion as achieved in a 4-stroke cycle but suppresses the gas exchange into the compression stroke.