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The earlier editions of this title have been best-selling definitive references for those needing technical information about automotive fuels. This long-awaited latest edition has been thoroughly revised and updated, yet retains the original fundamental fuels information that readers find so useful. This book is written for those with an interest in or a need to understand automotive fuels. Because automotive fuels can no longer be developed in isolation from the engines that will convert the fuel into the power necessary to drive our automobiles, knowledge of automotive fuels will also be essential to those working with automotive engines. Small quantities of fuel additives increasingly play an important role in bridging the gap that often exists between fuel that can easily be produced and fuel that is needed by the ever-more sophisticated automotive engine.

Small diesel engines are a common primer for micro and mini-grid systems, which can supply affordable electricity to rural and remote areas, especially in developing countries. These diesel generators have no exhaust after-treatment system thus exhaust emissions are high. This paper investigates the potential of introducing simulated synthetic gas (syngas) to diesel in a small diesel engine to explore the opportunities of widening fuel choices and reducing emissions using a 5.7kW single cylinder direct injection diesel generator engine. Three different simulated syngas blends (with varying hydrogen content) were prepared to represent the typical syngas compositions produced from downdraft gasification and were injected into the air inlet. In-cylinder pressure, ignition delay, premixed combustion, combustion stability, specific energy consumption (SEC), and gaseous and particle emissions were measured at various power settings and mixing ratios.

Developed by Rudolph Diesel in the 1890s, the diesel powertrain is used in many applications worldwide. For significant time the engine fuel source for these engines was petroleum diesel, until new legislation regarding emission reduction and smog mitigation saw the introduction of petroleum diesel and biodiesel (Fatty acid methyl ester; FAME) blends in the early 2000s. Since then there have been many instances of filters in diesel powertrains across heavy, light and off-road platforms becoming blocked with unidentified material, for example in the United States, Northern Europe and Scandinavia. Filters are designed to remove contaminants from the fuel system and as the filter becomes plugged it restricts the fuel flow resulting in loss of engine power and eventual breakdown. Understanding The nature of the material responsible for such blockages is clearly important to the industry and has been the subject of many studies.

The increased severity and prevalence of insoluble deposits formed on fuel injectors in gasoline direct injection (GDI) engines precipitates negative environmental, economic and healthcare impacts. A necessary step in mitigating deposits is to unravel the molecular compositions of these complex layered materials. But very little molecular data has been acquired. Mass spectrometry shows promise but most techniques require the use of solvents, making them unsuited for analyzing insoluble deposits. Here, we apply the high mass-resolving power and in-situ analysis capabilities of 3D OrbitrapTM secondary ion mass spectrometry (3D OrbiSIMS) to characterize deposits formed on the external tip and internal needle from a GDI injector. This is the first application of the technique to study internal GDI deposits. Polycyclic aromatic hydrocarbons (PAHs) are present up to higher maximum masses in the external deposit.

A Gas to liquid (GTL) fuel was investigated for its combustion and emission performance in an IVECO EURO5 DI diesel engine with a DOC (Diesel Oxidation Catalyst) and DPF (Diesel Particle Filter) installed. The composition of the GTL fuel was analyzed by GC-MS (gas chromatography-mass spectrometry) and showed the carbon distribution of 8-20. Selected physical properties such as density and distillation were measured. The GTL fuel was blended with standard fossil diesel fuel by ratios of diesel/GTL: 100/0, 70/30, 50/50, 30/70 and 0/100. The engine was equipped with a pressure transducer and crank angle encoder in one of its cylinders. The properties of ignition delay and maximum in-cylinder pressure were studied as a function of fraction of the GTL fuel. Particle emissions were measured using DMS500 particle size instrument at both upstream (engine out) and downstream of the DPF (DPF out) for particle number concentrations and size distribution from 5 nm to 1000 nm.

Over the last decade, there has been an impetus in the automobile industry to develop new diesel injector systems, driven by a desire to reduce fuel consumption and proscribed by the requirement to fulfil legislation emissions. The modern common-rail diesel injector system has been developed by the industry to fulfil these aspirations, designed with ever-higher tolerances and pressures, which have led to concomitant increases in fuel temperatures after compression with reports of fuel temperatures of ~150°C at 1500-2500 bar. This engineering solution in combination with the introduction of Ultra Low Sulphur diesel fuel (ULSD) has been found to be highly sensitive to deposit formation both external injector deposits (EDID) and internal (IDID). The deposits have caused concerns for customers with poor spray patterns misfiring injector malfunction and failure, producing increased fuel consumption and emissions.

Heat Release Rate (HRR) analysis is indispensable in engine research. The HRR of Internal Combustion Engines (ICEs) is most sensitive to gamma (γ). The proposed HRR models in literature were largely based on γ expressed as functions of temperature. However, γ is depended on temperature as well as the excess air ratio (λ). In this work, an improved HRR model based on γ(T, λ) was used to investigate the combustion behaviour of standard diesel, Gas-to-Liquid (GTL) diesel and Hydrotreated Vegetable Oil (HVO) diesel in a 96 kW, multiple fuel injection, Euro V, Direct Injection (DI) engine. The improved HRR model (Leeds HRR model) was validated for the alternative fuels by comparing the fuel masses predicted by the model to the measured fuel masses. The fuel masses predicted by the Leeds HRR model were also compared to the predictions from four HRR models that were based on γ(T).

The impact of internal diesel injector deposits (IDIDs) on engine performance, efficiency and emissions remains a major concern in the automotive industry. This has been compounded in recent years by fuel injection equipment developments and changes to diesel fuel towards ultra-low sulfur diesel (ULSD) and biodiesel as well as the introduction of new fuels such as hydrotreated vegetable oil (HVO). Prevention and mitigation of such deposit formation requires an understanding of the formation process, which demands a chemical explanation. The chemistry of these deposits therefore remains a key research interest to the industry using the latest analytical methodologies to inform and build further on previous investigations.

This paper presents the PN (Particle Number) and some gaseous emissions results from a group of SI (Spark Ignition) passenger cars including HEV (Hybrid Electric Vehicle), PFI (Port Fuel Injection) and GDI (Gasoline Direction Injection) vehicles. The PEMS (Portable Emission Measurement System) was used for on-board emission measurements. The vehicles were driven using the routes complying with the EU Real Driving Emissions (RDE) test procedures required in the European Commission Regulation (EU) 2016/427, i.e. starting in an urban driving mode and then continuing into a rural driving mode and ending with motorway driving mode part. The percentage of these three segments is approximately 33%, 33%, 33% respectively. The total test time was between 90 to 120 minutes. The vehicles’ driving parameters such as road speed, tailpipe exhaust temperatures and energy consumption were recorded and their correlations with emissions were investigated.

Light-duty China-6, which is among the most stringent vehicle exhaust emission standards globally, mandates the monitoring and reporting of real driving emissions (RDE) from July, 2023. In the process of regulation promulgation and verification, more than 300 RDE tests have been performed on over 50 China-5 and China-6 certified models. This technical paper endeavors to summarize the experience of RDE practice in China, and discuss the impacts of some boundary conditions (including vehicle dynamic parameters, data processing methods, hybrid propulsion and testing altitude) on the result of RDE measurement. In general, gasoline passenger cars confront few challenges to meet the upcoming RDE NOx requirement, but some China-5 certified samples, even powered by naturally-aspirated engines may have PN issues. PN emissions from some GDI-hybrid powertrain systems also need further reduction to meet China-6 RDE requirements.

Studies of diesel system deposits continue to be the subject of interest and publications worldwide. The introduction of high pressure common rail systems resulting in high fuel temperatures in the system with the concomitant use of fuels of varying solubilizing ability (e.g. ULSD and FAME blends) have seen deposits formed at the tip of the injector and on various internal injector components. Though deposit control additives (DCAs) have been successfully deployed to mitigate the deposit formation, work is still required to understand the nature and composition of these deposits. The study of both tip and internal diesel injector deposits (IDID) has seen the development of a number of bench techniques in an attempt to mimic field injector deposits in the laboratory. One of the most used of these is the Jet Fuel Thermal Oxidation Tester or JFTOT (ASTM D3241).

Hydrogenated Vegetable Oil (HVO) diesel fuels have the potential to provide a reduced carbon footprint for diesel engines and reduce exhaust emissions. Therefore, it is a strong candidate for transport and diesel powered machines including electricity generators and other off-road machines. In this research, a waste cooking oil derived HVO diesel was investigated for its combustion and emission performance including ignition delays, size segregated particulate number emissions and gaseous emissions. The results were compared to the standard petroleum diesel. A EURO5 emission compliant three litre, direct injection, intercooled IVECO diesel engine equipped with EGR was used which has a maximum power output of 96kW. The engine was equipped with an integrated DOC and DPF aftertreatment system. Both the upstream and downstream of the aftertreatment emissions were measured. The tests were conducted at different RPM and loads at steady state conditions.

To maximize CO2 reduction, refined straight used cooking oils were used as a fuel in Heavy Goods Vehicles (HGVs) in this research. The fuel is called C2G Ultra Biofuel (C2G: Convert to Green Ltd) and is a fully renewable fuel made as a diesel replacement from processed used cooking oil, used directly in diesel engines specifically modified for this purpose. This is part of a large demonstration project involving ten 44-tonne trucks using C2G Ultra Biofuel as a fuel to partially replace standard diesel fuels. A dual fuel tank containing both diesel and C2G Ultra Biofuel and an on-board fuel blending system-Bioltec system was installed on each vehicle, which is able to heat the C2G Ultra Biofuel and automatically determine the required blending ratio of diesel and C2G Ultra Biofuel according to fuel temperature and engine load. The engine was started with diesel and then switched to C2G Ultra Biofuel under appropriate conditions.

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.

Since 2009, there has been a rise in deposits of various types found in diesel fuel injection systems. They have been identified in the filter, the injector tip and recently inside the injector. The latter internal diesel injector deposits (IDIDs) have been the subject of a number of recent publications, and are the subject of investigations by CRC (Central Research Council Diesel Performance Group-Deposit Panel Bench/ Rig Investigation sub panel) in the US and CEN (Committee European de Normalisation TC19/WG24 Injector Deposit Task Force) and CEC (Coordinating European Council TDFG-110 engine test) in Europe. In the literature one of the internal injector deposit types, amide lacquers, has been associated with a poorly characterised noncommercial low molecular weight polyisobutylene succinimide detergent which also lacked provenance.

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.

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.

In order to improve energy supply diversity and reduce carbon dioxide emissions, sustainable bio-fuels are strongly supported by EU and other governments in the world. While the feedstock of biofuels has caused a debate on the issue of sustainability, the used cooking oil (UCO) has become a preferred feedstock for biodiesel manufacturers. However, intensive energy consumption in the trans-esterification process during the UCO biodiesel production has significantly compromised the carbon reduction potentials and increased the cost of the UCO biodiesel. Moreover, the yield of biodiesel is only ∼90% and the remaining ∼10% feedstock is wasted as by-product glycerol. Direct use of UCO in diesel engines is a way to maximize its carbon saving potentials.

The nature of internal diesel injector deposits (IDID) continues to be of importance to the industry, with field problems such as injector sticking, loss of power, increased emissions and fuel consumption being found. The deposits have their origins in the changes in emission regulations that have seen increasingly severe conditions experienced by fuels because of high temperatures and high pressures of modern common rail systems and the introduction of low sulphur fuels. Furthermore, the effect of these deposits is amplified by the tight engineering tolerances of the moving parts of such systems. The nature and thus understanding of such deposits is necessary to both minimising their formation and the development of effective diesel deposit control additives (DCA).