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Regulations have been established for the monitoring and reporting of greenhouse gas (GHG) emissions and fuel consumption from the transport sector. Low carbon fuels combined with new powertrain technologies have the potential to provide significant reductions in GHG emissions while decreasing the dependence on fossil fuel. In this study, a lean-burn ethanol-diesel dual-fuel combustion strategy has been used as means to improve upon the efficiency and emissions of a conventional diesel engine. Experiments have been performed on a 2.0 dm3 single cylinder heavy-duty engine equipped with port fuel injection of ethanol and a high-pressure common rail diesel injection system. Exhaust emissions and fuel consumption have been measured at a constant engine speed of 1200 rpm and various steady-state loads between 0.3 and 2.4 MPa net indicated mean effective pressure (IMEP).

Diesel engine cold-start problems include long cranking periods, hesitation and white smoke emissions. A better understanding of these problems is essential to improve diesel engine cold-start. In this study computer simulation model is developed for the steady state and transient cold starting processes in a single-cylinder naturally aspirated direct injection diesel engine. The model is verified experimentally and utilized to determine the key parameters that affect the cranking period and combustion instability after the engine starts. The behavior of the fuel spray before and after it impinges on the combustion chamber walls was analyzed in each cycle during the cold-start operation. The analysis indicated that the accumulated fuel in combustion chamber has a major impact on engine cold starting through increasing engine compression pressure and temperature and increasing fuel vapor concentration in the combustion chamber during the ignition delay period.

Main topics are the development and the build-up of an 18ton hybrid truck with a parallel hybrid drivetrain. With this truck it is possible to drive up to 3 kilometers in the pure electric driving mode. Presenter Andreas Eglseer, Engineering Center Steyr GmbH & Co. KG

With a growing need for a more efficient consumer based automotive platform, Embry-Riddle Aeronautical University (ERAU) chose to redesign the 2013 Chevrolet Malibu as a Plug-in Hybrid Electric Vehicle(PHEV). A Series architecture was chosen for its low energy consumption and high consumer acceptability when compared to the Series/Parallel-through-the-road and the Pre-Transmission designs. A fuel selection process was also completed and B20 Biodiesel was selected as the primary fuel due to lower GHG (Greenhouse Gases) emissions and Embry-Riddle's ability to produce biodiesel onsite using the cafeteria's discarded vegetable oil.

After-treatment sensors are used in the ECU feedback control to calibrate the engine operating parameters. Due to their contact with exhaust gases, especially NOx sensors are prone to soot deposition with a consequent decay of their performance. Several phenomena occur at the same time leading to sensor contamination: thermophoresis, unburnt hydrocarbons condensation and eddy diffusion of submicron particles. Conversely, soot combustion and shear forces may act in reducing soot deposition. This study proposes a predictive 3D-CFD model for the analysis of the development of soot deposition layer on the sensor surfaces. Alongside with the implementation of deposit and removal mechanisms, the effects on both thermal properties and shape of the surfaces are taken in account. The latter leads to obtain a more accurate and complete modelling of the phenomenon influencing the sensor overall performance.

This study utilized a 4-valve engine under HCCI combustion conditions. Each side of the split intake port was fed independently with different temperatures and reactant compositions. Therefore, two stratification approaches were enabled: thermal stratification and compositional stratification. Argon was used as a diluent to achieve higher temperatures and stratify the in-cylinder temperature indirectly via a stratification of the ratio of specific heats (γ = cp/cv). Tests covered five operating conditions (including two values of A/F and two loads) and four stratification cases (including one homogeneous and three with varied temperature and composition). Stratifications of the reactants were expected to affect the combustion control and upper load limit through the combustion phasing and duration, respectively. The two approaches to stratification both affect thermal unmixedness. Since argon has a high γ, it reached higher temperatures through the compression stroke [1].

A computational and experimental study was performed to characterize the flow within a gasoline injector and the ensuing sprays. The computations included the effects of turbulence, cavitation, flash-boiling, compressibility, and the presence of non-condensible gases. The flow domain corresponded to the Engine Combustion Network's Spray G, an eight-hole counterbore injector operating in a variety of conditions. First, a rate tube method was used to measure the rate of injection, which was then used to define inlet boundary conditions for simulation. Correspondingly, injection under submerged conditions was simulated for direct comparison with experimental measurements of discharge coefficient. Next, the internal flow and external spray into pressurized nitrogen were simulated under the base spray G conditions. Finally, injection under flashing conditions was simulated, where the ambient pressure was below the vapor pressure of the fuel.

A compact, lightweight compression-ignition engine designed for high fuel economy and low emissions was developed by ISUZU for the GM PNGV vehicle. This engine was the key component in the selected parallel hybrid vehicle powertrain for the 80 mpg fuel economy target. The base hardware was derived from a 1.7 Liter, 4-cylinder engine, and a three-cylinder version was created for the PNGV application. To achieve the required high efficiency, the engine used lightweight components thus minimizing weight and friction. To reduce exhaust emissions, electromechanical actuators were used for EGR, intake throttle, and turbocharger. Through careful application of these devices and combustion development, stringent engine out exhaust emission targets were also met.

Engine oil specifications have been changing since the invention of the automobile and the internal combustion engine. The industry associations that have played a key role in engine oil specification development have changed or evolved in fairly regular time intervals. The specifications, the tests behind the specifications, and the groups involved in shaping the specifications are discussed from a historical and present day perspective.

The paper includes the development steps used in creating a station test apparatus (STA) and a description of the apparatus design. The purpose of this device is to simulate hydrogen vehicle conditions for the verification of gaseous hydrogen refueling station dispenser performance targets and hydrogen quality. This is done at the refueling station/vehicle interface (i.e. the refueling nozzle.) In addition, the device is to serve as a means for testing and developing future advanced fueling algorithms and protocols. The device is to be outfitted with vehicle representative container cylinders and sensors located inside and outside the apparatus to monitor refueling rate, ambient and internal gas temperature, pressure and weight of fuel transferred. Data is to be recorded during refueling and graphed automatically.

The paper describes the challenges and results achieved in developing a new high-speed Diesel combustion system capable of exceeding the imaginative threshold of 100 kW/l. High-performance, state-of-art prototype components from automotive diesel technology were provided in order to set-up a single-cylinder research engine demonstrator. Key design parameters were identified in terms boost, engine speed, fuel injection pressure and injector nozzle flow rates. In this regard, an advanced piezo injection system capable of 3000 bar of maximum injection pressure was selected, coupled to a robust base engine featuring ω-shaped combustion bowl and low swirl intake ports. The matching among the above-described elements has been thoroughly examined and experimentally parameterized.

In this multi-phase study, fuel and lubricant effects on stochastic preignition (SPI) were examined. First, the behavior of fuels for which SPI data had previously been collected were characterized in terms of their combustion and emissions behavior, and correlations between these characteristics and their SPI behavior were examined. Second, new SPI data was collected for a matrix of fuels that was constructed to test and confirm hypotheses that resulted from interpretation of the earlier data in the study and from data in open literature. Specifically, the extent to which the presence of heavy components in the fuel affected SPI propensity, and the extent to which flame initiation propensity affected SPI propensity, were examined. Finally, the interaction of fuels with lubricants expected to exhibit a range of SPI propensities was examined.

Carbon, hydrogen and oxygen are major elements in vehicle fuels. Knowledge of fuels elemental composition is helpful in addressing its performance characteristics. Carbon, hydrogen and oxygen composition is an important parameter in engine calibration affecting vehicle performance, emissions and fuel economy. Biodiesel, a fuel comprised of mono-alkyl esters of long-chain fatty acids also known as Fatty Acid Methyl Esters(FAME), derived from vegetable oils or animal fats, has become an important commercial marketplace automotive fuel in the United States (US) and around the world over last few years. FAME biodiesels have many chemical and physical property differences compared to conventional petroleum based diesel fuels. Also, the properties of biodiesel vary based on the feedstock chosen for biodiesel production. One of the key differences between petroleum diesel fuels and biodiesel is the oxygen content.

A Soot-NOx Trap (SNT) is a combinatorial aftertreatment device intended to decrease both particulate and NOx emissions simultaneously. A system-level Soot-NOx Trap model was developed by adding Lean NOx Trap kinetics to a 1D Diesel Particulate Filter model. The hybrid model was validated against each parent model for the limiting cases, then exercised to investigate the interacting redox behavior. Modulations in temperature and exhaust air-fuel ratio were investigated for their ability to facilitate particulate oxidation and NOx reduction in the trap.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

The SAE FCV Safety Working Group has been addressing fuel cell vehicle (FCV) safety for over 8 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable to FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. J2578 is currently being updated to clarify and update requirements so that it will continue to be relevant and useful in the future. An update to SAE J1766 for post-crash electrical safety was also published to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to revising SAE J2578 and J1766, the Working Group is also developing a new Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has published and is developing standards for FCVs and hydrogen vehicles. SAE J2578 was the first document published by the working group. The document is written from an overall vehicle perspective and deals with the integration of fuel cell and hydrogen systems in the vehicle and the management of risks associated with these systems. Since the publishing of SAE J2578, the working group has updated SAE J1766 regarding post-crash electrical safety and is developing SAE J2579 which deals with vehicular hydrogen systems.

A laser sheet imaging system with Mie-scattering and Laser Induced Fluorescence (LIF) was used to investigate the spray characteristics of gasoline, methanol and ethanol fuels. A range of conditions found in today's gasoline engines were investigated including that observed during engine cold-start. Both a swirl injector and a multi-hole fuel injector were examined for each of the three fuels. A combination of the second harmonic (532 nm) and the fourth harmonic (266 nm) was generated simultaneously using a Nd:YAG laser system to illuminate the spray. The Mie-scattering technique was used to characterize the liquid phase of the spray while the LIF technique was used to detect a combination of liquid and vapor phases. While gasoline naturally fluoresced, the dopant TEA was added to the methanol and ethanol fuels as a fuel tracer. The Mie-scattering and LIF signals were captured simultaneously using a CCD camera along with an image doubler.

Ethanol for use in automotive fuels can be made from renewable feedstocks, which contributes to its increased use in recent years. There are many differences in physical and chemical properties between ethanol and petrochemicals refined from fossil oil. One of the differences is its energy content. The energy content, or heating value, is an important property of motor fuel, since it directly affects vehicle fuel economy. While the energy content can be measured by combustion of the fuel in a bomb, the test is time-consuming and expensive. It is generally satisfactory and more convenient to estimate that property from other commonly-measured fuel properties. Several standardized empirical methods have been developed in the past for estimating the energy content of hydrocarbon fuels such as gasoline, diesel fuel, and jet fuel.

The introduction of new light-duty vehicle emission limits to comply under real driving conditions (RDE) is pushing the diesel engine manufacturers to identify and improve the technologies and strategies for further emission reduction. The latest technology advancements on the after-treatment systems have permitted to achieve very low emission conformity factors over the RDE, and therefore, the biggest challenge of the diesel engine development is maintaining its competitiveness in the trade-off “CO2-system cost” in comparison to other propulsion systems. In this regard, diesel engines can continue to play an important role, in the short-medium term, to enable cost-effective compliance of CO2-fleet emission targets, either in conventional or hybrid propulsion systems configuration. This is especially true for large-size cars, SUVs and light commercial vehicles.