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As a result of research made during EuroBioRef, five alternative bio based diesel fuels have been produced and tested. The fuels consisted of three different products made from castor oil: Esterol A, Esterol Lot BP093 and Methyl-UCT. The two remaining fuels were POM-Methyl 2.8 and 3-Methylheptane. For the test, the fuels were blended with a reference diesel at a 30%vol ratio. The fuels were tested in a euro 4, 1.6L light-duty high-speed road going turbocharged engine with an EGR-system. The engine was configured with standard injectors and standard ECU settings. The tests were performed on an eddy current dynamometer in four different modes. Analysis shows that the NOx level increased slightly for Esterol A, Methyl-UCT and POM-methyl 2.8. It also showed that CO level was higher for POM-Methyl 2.8 and 3-Methylheptane during highest speed and load.

Hydrotreated vegetable oil (HVO) is a renewable high quality paraffinic diesel that can be obtained by the hydrotreating of a wide range of biomass feedstocks, including vegetable oils, animal fats, waste oils, greases and algal oils. HVO can be used as a drop-in fuel with beneficial effects for the engine and the environment. The main objective of this study was to explore the potential of HVO as a candidate bio blendstock for new experimental formulations of diesel fuel to be used in advanced combustion systems at different compression ratios and at high EGR rates in order to conform to the Euro 6 NOx emission standard. The experiments were carried out in a single-cylinder research engine at three steady-state operating conditions and at three compression ratios (CR) by changing the piston.

A new Alcohol To Jet (ATJ) fuel has been developed using a process which takes biomass feedstock to produce a branched butanol molecule. Further dehydration, reforming and hydro-treating produced principally a highly branched C12 iso-paraffin molecule. This ATJ fuel with a low cetane value (DCN = 18) was blended with Navy jet fuel (JP5) in various quantities and tested in order to determine how much ATJ could be blended before diesel engine operation became problematic (the US Navy and Marine Corps may use jet fuel in their diesel engines). Blends of 20%, 30% and 40% ATJ (by volume) were tested with jet fuel. The Derived Cetane Number (DCN) falls from 45 for the base JP5 to 38 with the 40% ATJ component blended in. Engine start performance was evaluated on two Yanmar engines and a Waukesha CFR diesel engine and showed that engine start times increased steadily with increasing ATJ content.

N-butanol is a promising alternative fuel which needs no engine modification when used as a blend with diesel. The miscibility of n-butanol with diesel is excellent in a wide range of blending ratios. N-butanol has high oxygen content and a comparable energy content, specific gravity and viscosity to that of diesel, which makes it attractive for diesel engines as an alternative fuel. An experimental investigation was conducted to assess the performance of a new generation passenger car with respect to power, fuel economy (FE) and mass emission using 5, 10 and 20 percent (by vol.) n-butanol blends with diesel (NB). Computer controlled DC motor driven chassis dynamometer, AVL AMA I60 mass emission measuring system and AVL FSN smoke meter were used for measuring wide open throttle (WOT) power, road load simulation (RLS) fuel economy, mass emissions and smoke in WOT and steady speed driving conditions.

Recent developments in advanced combustion engines have demonstrated the potential increases in efficiency and reductions in emissions through low temperature combustion (LTC). These combustion modes often rely on high exhaust gas recirculation (EGR), early fuel injection systems, and in some cases a combination of fuels with different reactivities. Despite the advantages of LTC, such operations are highly sensitive to the in-cylinder pre-combustion conditions and face significant challenges in multi-cylinder operation due to cylinder-to-cylinder variations of the combustion process. The cause of cylinder-to-cylinder variations is strongly tied to non-uniform trapped mass. In particular, in-cylinder oxygen concentration plays a critical role in the combustion process of each cylinder and can be leveraged to predict combustion characteristics and to develop control algorithms that mitigate cylinder-to-cylinder variation.

In this paper we have obtained real-time series of in-cylinder pressure by carrying out some experiments and studied the in-cylinder pressure cycle-to-cycle variations in a diesel engine. By using recurrence plot (RP) and recurrence quantification analysis (RQA), we have investigated the dynamical characteristics of combustion in diesel engine through the in-cylinder pressure cycle-to-cycle variations. The results show that the combustion process exhibits many chaotic features and deterministic nature, the qualitative and quantitative change in combustion can be easily related to patterns in recurrence plots (RPs) and RQA, and combustion system is sensitive to initial conditions. The conclusions of our research work may be helpful in developing effective control strategies to improve diesel engine performance.

Amidst the rising demand to reduce CO2 and other greenhouse gas emissions in recent years, gasoline homogeneous-charge compression ignition (HCCI) has gained attention as a technology that achieves both low NOx emissions and high thermal efficiency by means of lean combustion. However, gasoline HCCI has low robustness toward intracylinder temperature variations, therefore the problems of knocking and misfiring tend to occur during transient operation. The authors verified the transient operation control of HCCI by using a 4-stroke natural aspiration (NA) gasoline engine provided with direct injection (DI) and a variable valve timing and a lift electronic control system (VTEC) for intake air and exhaust optimized for HCCI combustion. This report describes stoichiometry spark ignition (SI) to which external exhaust gas recirculation (EGR) was introduced, HCCI ignition switch control, and changes in the load and number of engine revolutions in the HCCI region.

The performance of three different electric turbo-compounding systems under both steady and driving cycle condition is investigated in this paper. Three configurations studied in this paper are serial turbo-compounding, parallel turbo-compounding and electric assisted turbo-compounding. The electric power, global gain of the whole system (engine and power turbine) under steady operating condition is firstly studied. Then investigation under three different driving cycles is conducted. Items including fuel consumption, engine operating point distribution and transient response performance are analyzed among which the second item is done based on statistic method combined with the results obtained under steady operating conditions. Study under steady condition indicates that electric assisted turbo-compounding system is the best choice compared with the other two systems. The performance of serial turbo-compounding is load oriented while parallel configuration is speed oriented.

A search of the automotive collision trauma literature reveals that over the last 35 years shows that there have been less than ten published Society of Automotive Engineers (SAE) articles describing the collision effects and resulting human occupant kinematics in low speed side impact collisions. The aim of this study was to quantify the occupant response for both male and female occupants for a battery of low-speed side impacts with various impact speeds and configurations. Eight volunteers were used in a series of twenty-five staged side impact collisions with impact speeds ranging from approximately 2 km/h to 10 km/h and impact configurations to the front, middle and rear side portions of the vehicle. A NHTSA FMVSS 301 moving barrier was used as the impacting vehicle. A stiff bumper was constructed to fit the front of the barrier and was attached at a normal passenger vehicle bumper height. Occupant and vehicle responses were monitored by accelerometers and high-speed video.

A typical means of limiting the peak power output of race car engines is to restrict the maximum mass flow of air to the engine. The Formula SAE sanctioning body requires the use of an intake restrictor to limit performance, keep costs low, and maintain a safe racing experience. The intake restrictor poses a challenge to improving engine performance. Methods to better understand the ramifications of the restrictor on the engine lead to performance improvements that allow an edge over the competition. A one-dimensional gas exchange simulation code coupled with three-dimensional CFD is used to simulate various concepts in the improvement of restrictor performance. Ricardo's WAVE and VECTIS are the respective simulation codes. Along with this, the interaction of intake manifold and restrictor are considered. The effects of different diffuser geometries and plenum dimensions were first explored using WAVE, and then a series of different diffuser angles were simulated using WAVE-VECTIS.

Rolling element bearings are known to give reduced friction losses when compared to the hydrodynamic bearings typically used to support the crankshaft in multi-cylinder engines. This paper describes the design, manufacturing and testing of a modified 4 cylinder light duty Diesel production engine with rolling element bearings applied at the crankshaft main bearings in view of CO2 emission reduction. Selection of the most suitable type of roller bearings for this specific application was made. Technology development through multi-body dynamic simulation and component testing was done to assess the effect on rolling elements performance due to the key challenges inherent to such bearing solution: high instantaneous combustion load, lubrication with low viscosity and contaminated oil, and the cracking process to split the bearing outer raceway.

In low-speed, rear-end collisions, the occupant in the target vehicle moves rearward relative to the vehicle and interacts with the seatback and seat bottom. Due to the direct interaction of the occupant with the seat, seat stiffness can affect the kinematics of the occupant. Generic seat stiffness values are often used as input parameters in computer programs, such as MADYMO, that are used to model low-speed, rear-end collisions and simulate occupant kinematics. To create an accident specific simulation, the model could take into account all aspects of the accident including the person involved, the subject vehicle, and the subject vehicle seat. Recent research has demonstrated that the seat stiffness of the compressible structure of the seat, comprised of foam and springs, can vary between vehicles, and also can vary between regions within a single vehicle seat.

The future of the Hybrid Electric Vehicle (HEV) is very promising for the automotive industry. In order to take a full advantage of this concept, a better thermal performance of the electric motor is required. In this study, Computational Fluid Dynamics (CFD) model was first verified through several prototypes testing and then is going to be used to execute a series of design of experiment via simulation. Based on the thermal studies in this paper, the integrated coolant jacket design has a better performance than that of separated one. The thermal performance of the stator with the 3M coating is better than the one with paper liner. In addition, using 3M coating reduces the packaging size of the stator.

Delphi Diesel Systems' 2700bar Proven F2E Distributed Pump Common Rail System (DPCRS) has been developed to meet the requirements of Euro VI and future emissions legislation and is now in volume production in Heavy Duty Vehicles. Incorporating a number of ground breaking new technologies, the system offers numerous performance advantages. F2E provides full common rail functionality for camshaft driven Fuel Injection Equipment (FIE) engines with minimum modification. By delivering precise and accurate control of multiple injections at maximum rail pressure across all engine operating conditions, the system minimizes the demands on exhaust after treatment systems. Additionally F2E provides real time flexible capacity by employing a unique method of pump fuel metering, enabling the most efficient and accurate transient control of rail pressure combined with the low NVH and optimised efficiency.

Hot-formed steels, also called “Boron steels” or Ultra-High Strength Steels-UHSS, offer a great weight saving potential versus conventional cold-formed high strength steels used for crash relevant structural parts. Boron steels allow complex shaped parts due to the hot-forming process. In the hot forming process first the sheet metal with initial yield strength of around σy=400 MPa is blanked and then heated in an oven up to ∼950° Celsius. In the next step the “hot” sheet metal is stamped and at the same time rapidly cooled down and quench hardened in the stamping die. During this process the yield and ultimate tensile strength increase up to approximately σy>1100 MPa and UTS∼1500 MPa in the final stamped part. The enormous strength and the very good dimensional tolerances with nearly no springback result in the use of more and more hot-formed parts in the body, especially for crash relevant parts like structural reinforcements.

Since 1983 the Torsen® differential has been employed in the powertrain of more than two-dozen sedans, SUVs, and military vehicles. This differential device is renowned for its unique high torque bias capacity. Torque bias has long been recognized as a desirable drivetrain characteristic that enhances both a vehicle's drivability and stability. Since the generation of torque bias relies on friction, the know-how in achieving balanced design of torque bias and efficiency is crucial. Presented in this paper is an analytical evaluation of the performance of Torsen differential with respect to these parameters. The mathematical model provides effective guidance in design optimization. The performance predictions were found to correlate well with experimentally measured data. In an effort to explore the theory behind the Torsen differential design, the general subject of speed differentiation and torque bias generation is reviewed.

Occupants exposed to far-side crashes are those seated on the side of the vehicle opposite the struck side. This study uses the NASS/CDS 1988–98 to determine distributions of serious injuries among restrained occupants exposed to far-side crashes and the sources of the injuries. Vehicle-to-vehicle crash tests were conducted to study dummy kinematics. The NASS/CDS indicated that the head accounted for 45% of the MAIS 4+ injuries in far-side collisions and the chest/abdomen accounted for 39%. The opposite-side interior was the most frequent contact associated with driver AIS 3+ injuries (26.9%). The safety belt was second, accounting for 20.8%. Vehicle-to-vehicle side impact tests with a 60 degree crash vector indicated that different safety belt designs resulted in different amounts of head excursion for the far side Hybrid III dummy. For all three point belt systems tested, the shoulder belt was ineffective in preventing large amounts of head excursion.

There currently are only two industry wide utilized designs of standardized threaded connector for brake tubing. The ISO design incorporates a “bubble” style of tube's end-form while the JASO/SAE design includes double inverted “funnel” tube's flare. Both designs are based on the arrangement of two conical (frustum) surfaces which have to be pressed against each other in order to provide sealing. Seal integrity robustness of those standardized connectors is not sufficient as some retorquing is usually required in the course of the assembly process in order to seal a number of them. Accordingly each plant must allocate resources for the associated detection and rework process as they strive for zero leaks in the field. Numerous investigations and root cause analyses reveal some fundamental shortcomings in their sealing capability. In order to achieve sealed state of the connector some self-adjustment and certain degree of sustained deformation of its components is expected.

During a motorcycle accident, a rider’s helmet may dissipate energy to reduce the likelihood of serious brain injury. Novelty helmets lack the energy-absorbing layer between the comfort liner and the outer shell of the helmet. In this study, we compared the injury mitigation capabilities and associated brain injury potential of novelty helmets to three US DOT-approved motorcycle helmets. The analysis was performed using a drop tower system. Helmeted Hybrid-III and magnesium head-forms were dropped onto a slab of asphalt with contact to the upper, back region of the helmets. The first drop height was chosen to simulate a fall from the typical seated height of a rider on a cruising style bike, and the second height was chosen to yield an impact speed that conformed to the DOT testing requirements, 6 meters per second (13.4 mph). Resultant accelerations, head injury criterion (HIC), and probability of an AIS 4+ brain injury were calculated for each drop test.

Robust engineering is an integral part of the quality initiative, Design For Six Sigma (DFSS), in most companies to enable good designs and products for reliability and durability. Taguchi’s signal-to-noise ratio has been considered as a good performance index for robustness for many years. An alternate approach that is direct and simple for measuring robustness is proposed. In this approach, robustness is measured in terms of an augmented output response and it is a composite index of variation and efficiency of a system. This formulation represents an engineering design intent of a product in a statistical sense, so engineers can understand, communicate, and resonate at ease. Robust formulations are illustrated and discussed with case studies for smaller-the-better, nominal-the-best, and dynamic responses. Confirmation runs of optimization show good agreement of the augmented response with the additive predictive models.