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The internal combustion engine and associated powertrain are likely to remain the mainstay of mobility over the next twenty years and to remain a significant portion of the portfolio of technologies employed over a much longer period of time. Efficient combustion of all fuels (petroleum based or alternative) requires copious amounts of air particularly with downsized engines. Turbocharging technology thus becomes an even more critical part of reducing both global warming gas and urban pollutant emissions from IC engines. Gasoline engine downsizing and turbocharging have been shown to improve fuel economy by ∼20% in production vehicles. In addition to data over a wide range of engines/vehicles, the results of a simple analysis done on vehicles/engines/drive cycles are presented to show the benefits of turbocharging and downsizing in a parametric variation of downsizing in combination with other technologies.

The embedded software has played an increasing role in safety-critical systems. At the same time the current development process of “build, then integrate” has proven unaffordable for the Aerospace industry. This paper outlines challenges in safety-critical embedded systems in addressing system-level faults that are currently discovered late in the development life cycle. We then discuss an architecture-centric approach to model-based engineering, i.e., to complement the validation of systems with analysis of different operational quality aspects from an architecture model. A key technology in this approach is the Architecture Analysis & Design Language (AADL), an SAE International standard for embedded software system. It supports analysis of operational qualities such as responsiveness, safety-criticality, security, and reliability through model annotations.

The study measured Mass Air Flow, (MAF), Manifold Absolute Pressure, (MAP), and emissions of NO and soot during fourteen transients of speed and load, representative of the Extra Urban Drive Cycle (EUDC). The tests were conducted on a typical passenger car/light-duty truck powertrain (a turbocharged common-rail diesel engine, of in-line 4-cylinder configuration). The objective was to compare NO and soot with corresponding steady-state emission results and propose an engine measurement methodology that will potentially quantify deviation (i.e. deterioration with respect to steady state optimum) in emissions of NO and soot during transients. Comparison between steady state, quasi-steady-states (defined later in the paper) and transients indicated that discrete quasi-steady-state engine operation, can be used for accurate prediction of transient emissions of NO and soot.

The paper discusses the concept, specification and performance of a new, dedicated range extender engine for plug-in series hybrid vehicles conceived and designed by Lotus Engineering. This has been undertaken as part of a consortium project called Limo Green, part-funded by the UK government. The Lotus Range Extender engine has been conceived from the outset specifically as an engine for a plug-in series hybrid vehicle, therefore being free of some of the constraints placed on engines which have to mate to conventional, stepped mechanical transmissions. The paper starts by defining the philosophical difference between an engine for range extension and an engine for a full series hybrid vehicle, a distinction which is important with regard to how much power each type must produce. As part of this, the advantages of the sparkignition engine over the diesel are outlined.

Experimental decklids for the Cadillac STS sedan were made with Al AA5083 sheet outer panels and Mg AZ31B sheet inner panels using regular-production forming processes and hardware. Joining and coating processes were developed to accommodate the unique properties of Mg. Assembled decklids were evaluated for dimensional accuracy, slam durability, and impact response. The assemblies performed very well in these tests. Explicit and implicit finite element simulations of decklids were conducted, and showed that the Al/Mg decklids have good stiffness and strength characteristics. These results suggest the feasibility of using Mg sheet closure panels from a structural perspective.

The global use of biodiesel fuel blends derived from fatty acid methyl esters (FAME) is increasing; driven by legislation derived from political, economic and environmental factors. The presence of FAME biodiesel changes the operating environment of the engine and after treatment devices, affecting the performance characteristics and requirements of the lubricant. As part of a wider research project into the impact of biologically-sourced fuels on crankcase lubricant performance, this paper documents the impact of biodiesel on corrosion-related performance. The effect of FAME biodiesel on lubricant corrosion control and the differences in performance due to FAME source are described. Mechanistic studies into the corrosive nature of FAME are reported. Novel lubricant technologies tailored to control the negative impact of FAME in the crankcase are demonstrated.

Organic acid degradation products and other anions in engine oil were speciated by capillary electrophoresis (CE) and liquid chromatography-mass spectrometry (LCMS) with electrospray ionization. The sample preparation procedure involved selectively extracting the acids and other water soluble salts into 0.05M aqueous potassium hydroxide. Samples of engine-aged mineral oil and synthetic engine oil contained formic acid, acetic acid, and complex mixtures of fatty acid degradation products. CE analysis of formic acid, acetic acid and selected fatty acids is proposed as a new chemical analysis method for evaluating the condition of engine oil and for studying the effects of high temperature-high load (HTHL) oxidation. Because the overall pattern of CE peaks in the electropherogram changes with oil age or condition, CE-fingerprint (i.e., pattern recognition) techniques may also be useful for evaluating an aged oil's condition or remaining service life.

The capability of theoretical durability studies to offer an efficient alternative methodology for predicting the potential performance of catalysts has improved in recent years. In this regard, multi-scale theoretical methods for predicting sintering behavior of Pt on various catalyst supports are being developed. Various types of Pt diffusions depending on support were confirmed by the micro-scale ultra accelerated quantum chemical molecular dynamics (UA-QCMD) method. Moreover, macro-scale sintering behavior of Pt/ɣ-Al2O3, Pt/ZrO2 and Pt/CeO2 catalyst were studied using a developed 3D sintering simulator. Experimental results were well reproduced. While Pt on ɣ-Al2O3 sintered significantly, Pt on ZrO2 sintered slightly and Pt on CeO2 demonstrated the highest stability against sintering.

In the present work, an experimental and numerical analysis of high pressure Diesel spray evolution is carried out in terms of spray momentum flux time history and instantaneous injection rate. The final goal of spray momentum and of injection rate analyses is the evaluation of the nozzle outlet flow characteristics and of the nozzle internal geometry possible influences on cavitation phenomena, which are of primary importance for the spray evolution. Further, the evaluation of the flow characteristics at the nozzle exit is fundamental in order to obtain reliable boundary conditions for injection process 3D simulation. In this paper, spray momentum data obtained in ambient temperature, high counter-pressure conditions at the Perugia University Spray Laboratory are presented and compared with the results of 3D simulations of the momentum rig itself.

Accelerated life testing (ALT) is widely used to determine the failure time distribution of a product and the associated life-stress relationship in order to predict the product's reliability under normal operating conditions. Many types of stress loadings such as constant-stress, step-stress and cyclic-stress can be utilized when conducting ALT. Extensive research has been conducted on the analysis of ALT data obtained under a specified stress loading. However, the equivalency of ALT experiments involving different stress loadings has not been investigated. In this paper, a definition is provided for the equivalency of various ALT plans involving different stress loadings. Based on this definition, general equivalent ALT plans and some special types of equivalent ALT plans are explored. For demonstration, a constant-stress ALT and a ramp-stress ALT for miniature lamps are presented and their equivalency is investigated.

As the number of electrical devices in modern vehicles increases, the battery becomes more critical component for the operation of vehicles. To ensure the startability of the vehicle, battery conditions such as state of charge and state of health should be properly monitored and maintained. To reduce walk-home incidents due to no-start situation, appropriate warning should be issued to the driver to advise necessary actions such as replacing or re-charging the battery. For the last couple of years, General Motors has studied and developed several battery health monitoring methods based on different battery health signatures. Yet, it is found that relying on a single method may lead to false alarm or misdetection due to lack of information or uncertainty. This paper develops the algorithm for more robust and reliable battery health monitoring and prognosis, by applying Evidence Theory to fuse different battery health signatures.

There is a wide spectrum of cast ferrous heat resistant alloys available for exhaust component applications such as exhaust manifolds and turbocharger housings. Generally speaking, the ferrous alloys can be divided into four groups including: ferritic cast irons, austenitic cast irons, ferritic stainless steels, and austenitic stainless steels. Selection of a suitable alloy usually depends on a number of material properties meeting the requirements of a specific application. Ferritic cast irons continue to be an important alloy for exhaust manifolds and turbocharger housings due to their relatively low cost. A better understanding of the alloying effects and graphite morphologies of ferritic cast irons are discussed and their effect on material behavior such as the brittleness at medium temperatures is provided. The nickel-alloyed austenitic cast irons, also known as Ni-resist, exhibit stable structure and improved high-temperature strength compared to the ferritic cast irons.

A simulation-based, system reliability-based design optimization (RBDO) method is presented that can handle problems with multiple failure regions and correlated random variables. Copulas are used to represent the correlation. The method uses a Probabilistic Re-Analysis (PRRA) approach in conjunction with a trust-region optimization approach and local metamodels covering each trust region. PRRA calculates very efficiently the system reliability of a design by performing a single Monte Carlo (MC) simulation per trust region. Although PRRA is based on MC simulation, it calculates “smooth” sensitivity derivatives, allowing therefore, the use of a gradient-based optimizer. The PRRA method is based on importance sampling. It provides accurate results, if the support of the sampling PDF contains the support of the joint PDF of the input random variables. The sequential, trust-region optimization approach satisfies this requirement.

Exhaust manifolds and turbocharger housings require good elevated temperature strength, good resistance to thermal fatigue and a stable microstructure. High silicon ductile iron, high silicon-molybdenum ductile iron and Ni-resist (a high nickel ductile iron) are the cast materials of choice. Unfortunately, molybdenum and nickel are expensive. In this study, a lower cost, high silicon-titanium, compacted graphite iron was developed and compared to high silicon ductile iron and higher cost, high silicon-molybdenum ductile iron. Room and elevated temperature strength data is presented.

A new liquid surface conditioner has been developed to improve phosphate coating quality and enable a low-temperature phosphating system designed to reduce CO₂ emissions during the pretreatment processes of automobile production. Phosphate film is formed by a phosphating treatment that provides corrosion resistance for the steel plates that make up auto bodies. In the vehicle body, pocket-shaped structures such as side sills and wheel arches are likely to collect muddy water and form rust. Regarding anticorrosion quality assurance, particular attention must be paid to these pocket structures, in which phosphating solution flows slowly, and a lower solution-volume-to-surface-area ratio contributes less to the phosphating reaction. For this reason, with the conventional liquid surface conditioner, a low-temperature phosphating system cannot coat substrate surfaces sufficiently, which would result in lower corrosion resistance.

Structural adhesive joints are expected to retain integrity in their entire service-life that normally involves cyclic loading concurrent with environmental exposure. Under such a severe working condition, effective determination of fatigue life at different temperatures is crucial for reliable joint design. The main goal of this work was thus defined as evaluation of fatigue performance of adhesive joints at their extreme working temperatures in order to be compared with their fracture properties under static loading. A series of standard double-cantilever-beam (DCB) specimens have been bonded by three structural 3M epoxy adhesives selected from different applications. The specimens were tested under monotonic and cyclic opening loads (mode-I) in order to evaluate the quasi-static and fatigue performances of selected adhesives at room temperature, 80°C and -40°C.

This paper deals with experimental study of in-cylinder tumble flows in a single-cylinder, four-stroke, two-valve internal combustion engine using a pentroof-offset-bowl piston under non-reacting conditions with four intake manifold orientations at an engine speed of 1000 rev/min., during suction and compression strokes using particle image velocimetry. Two-dimensional in-cylinder tumble flow measurements and analysis are carried out in combustion space on a vertical plane passing through cylinder axis. Ensemble average velocity vectors are used to analyze the tumble flows. Tumble ratio (TR) and average turbulent kinetic energy (TKE) are evaluated and used to characterize the tumble flows. From analysis of results, it is found that at end of compression stroke, 90° intake manifold orientation shows an improvement in TR and TKE compared other intake manifold orientations considered.

Incremental Sheet Forming (ISF) is an emerging sheet metal prototyping technology where a part is formed as one or more stylus tools are moving in a pre-determined path and deforming the sheet metal locally while the sheet blank is clamped along its periphery. A deformation analysis of incremental forming process is presented in this paper. The analysis includes the development of an analytical model for strain distributions based on part geometry and tool paths; and numerical simulations of the forming process with LS-DYNA. A skew cone is constructed and used as an example for the study. Analytical and numerical results are compared, and excellent correlations are found. It is demonstrated that the analytical model developed in this paper is reliable and efficient in the prediction of strain distributions for incremental forming process.

Boosted Homogeneous Charge Compression Ignition (HCCI) has been modeled and has demonstrated the potential to extend the engine's upper load limit. A commercially available engine simulation software (GT-PowerÖ) coupled to the University of Michigan HCCI combustion and heat transfer correlations was used to model a 4-cylinder boosted HCCI engine with three different boosting configurations: turbocharging, supercharging and series turbocharging. The scope of this study is to identify the best boosting approach in order to extend the HCCI engine's operating range. The results of this study are consistent with the literature: Boosting helps increase the HCCI upper load limit, but matching of turbochargers is a problem. In addition, the low exhaust gas enthalpy resulting from HCCI combustion leads to high pressures in the exhaust manifold increasing pumping work. The series turbocharging strategy appears to provide the largest load range extension.

In this study, a full vehicle with advanced LMS comfort and durability tire (CDT) model was established with ADAMS software to predict the spindle loads of the vehicle under a severe proving ground rough road event. From a series of simulations with various design changes, the spindle loads sensitivities to those design changes were identified. The simulated results were also compared with the measured data and a good correlation was achieved.