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The distribution of lubricating oil plays a critical role in determining the friction between piston skirt and cylinder liner, which is one of the major contributors to the total friction loss in internal combustion engines. In this work, based upon the experimental observation an existing model for the piston secondary motion and skirt lubrication was improved with a physics-based model describing the oil film separation from full film to partial film. Then the model was applied to a modern turbo-charged SI engine. The piston-skirt FMEP predicted by the model decreased with larger installation clearance, which was also observed from the measurements using IMEP method at the rated. It was found that the main period of the cycle exhibiting friction reduction is in the expansion stroke when the skirt only contacts the thrust side for all tested installation clearances.

Lubricating oil consumption (LOC) is a direct source of hydrocarbon and particulate emissions from internal combustion engines. LOC also inhibits the lifetime of exhaust aftertreatment system components, preventing their ability to effectively filter out other harmful emissions. Due to its influence on piston ring- bore conformability, bore distortion is arguably the most critical parameter for engine designers to consider in prevention of LOC. Bore distortion also has a significant influence on the contact forces between the piston ring and cylinder wall, which determine the wear rate of the ring and cylinder wall and can cause durability issues. Two drivers of bore distortion: thermal expansion and head bolt stresses, are routinely considered in conformability and contact analyses. Separately, bore distortion/vibration due to piston impact and combustion/cylinder pressures has been previously analyzed in wet liner engines for coolant cavitation and noise considerations.

In an engine system, the piston pin is subjected to high loading and severe lubrication conditions, and pin seizures still occur during new engine development. A better understanding of the lubricating oil behavior and the dynamics of the piston pin could lead to cost- effective solutions to mitigate these problems. However, research in this area is still limited due to the complexity of the lubrication and the pin dynamics. In this work, a numerical model that considers structure deformation and oil cavitation was developed to investigate the lubrication and dynamics of the piston pin. The model combines multi-body dynamics and elasto-hydrodynamic lubrication. A routine was established for generating and processing compliance matrices and further optimized to reduce computation time and improve the convergence of the equations. A simple built-in wear model was used to modify the pin bore and small end profiles based on the asperity contact pressures.

To improve the fuel economy, we developed a turbo-charged spark ignition engine combined with a low pressure loop EGR system. A negative pressure control valve has been applied to achieve high EGR ratio in wide engine operation condition. In this paper, a new developed model-based control system for low pressure loop EGR with a negative pressure control valve will be described.

A gasoline particulate filter (GPF) is installed in a passenger vehicle for new exhaust regulation. However, ash in gasoline engine oil has a risk of clogging as well as performance decrease in the GPF. Therefore, new gasoline engine oil whose ash contents decrease to 0.8 mass% was developed in order to avoid the GPF clogging. In addition to this, our developed oil improves fuel efficiency (+0.2% from our SN 0W-16 fuel eco type oil) as well as anti-wear performance for gasoline engine, which resulted in meeting API SP/ILSAC GF-6 0W-16 official certification.

Protecting the piston ring and liner interface is critical to the proper operation of internal combustion engines. Specifically, the dry region, which is the portion of the liner above the Top Dead Center (TDC) of the Oil Control Ring (OCR), needs proper lubrication to reduce wear and to maintain sustainability. However, the mechanisms by which oil is distributed to such region have not been investigated. This paper presents the first attempt to understand dry region lubrication by means of the oil-gas interaction below the top ring gap through a combination of experimental and modeling approaches. An optical engine with 2D Laser Induced Fluorescence (2D-LIF) technique was applied to visualize the oil flow below the top ring gap. It was observed that the two vortices downstream the top ring gap can cause oil bridging towards the liner, providing lubrication to the ring-liner interface.

The introduction of carburetor restrictor plates in NASCAR racing in 1988 necessitated the redesign of some engine components, such as the camshaft and exhaust headers, to re-optimize engine performance. This paper describes how an engine performance computer simulation code was used to quickly study the effects of the restrictor plate on the “breathing” processes of the Ford NASCAR V8 engine and determine the optimal intake and exhaust cam lobe profiles to maximize wide-open throttle torque and horsepower. The resulting camshaft design produced over 40 additional horsepower and greater average torque over the useful engine speed range for super speedways. The interaction between exhaust wavedynamics (i.e., “tuning”) and cam events was investigated and shown to be of critical importance to the optimization of the engine's trapping efficiency.

This book presents an analysis on the potential effects of globalization on the automotive industry and the environment. Energy challenges, market economy growth, and population dynamics are considered. The authors also present future scenarios for transportation technologies to meet the ever growing global demand for transportation of goods and services while minimizing energy and environmental impacts and maximizing cost, value and widespread acceptance.

Mo-free 1.6-GPa bolt was developed for a Variable Compression Turbo (VC-Turbo) engine, which is environment friendly and improves fuel efficiency and output. Mo contributes to the improvement of delayed fracture resistance; therefore, the main objective is to achieve both high strength and delayed fracture resistance. Therefore, Si is added to the developed steel to achieve high strength and delayed fracture resistance. The delayed fracture tests were performed employing the Hc/He method. Hc is the limit of the diffusible hydrogen content without causing a delayed fracture under tightening, and He is the diffusible hydrogen content entering under a hydrogen-charging condition equivalent to the actual environment. The delayed fracture resistance is compared between the developed steel and the SCM440 utilized for 1.2-GPa class bolt as a representative of the current high-strength bolts.

Internal combustion (IC) engines still power most of the vehicles on road and will likely to remain so in the near future, especially for heavy duty applications in which electrification is typically more challenging. Therefore, continued improvements on IC engines in terms of efficiency and longevity are necessary for a more sustainable transportation sector. Two important design objectives for heavy duty engines with wet liners are to reduce friction loss and to lower the risks of cavitation damages, both of which can be greatly influenced by the piston-liner clearance and the design of the piston skirt. However, engine design optimization is difficult due to the nonlinear interactions between the key design variables and the design objectives, as well as the multi-physics and multi-scale nature of the mechanisms that are relevant to the design objectives.

A new diesel engine, called the 6.7L Power Stroke® V-8 Turbo Diesel, and code named "Scorpion," was designed and developed by Ford Motor Company for the full-size pickup truck and light commercial vehicle markets. The combustion system includes the piston bowl, swirl level, number of nozzle holes, fuel spray angle, nozzle tip protrusion, nozzle hydraulic flow, and nozzle-hole taper. While all of these parameters could be explored through extensive hardware testing, 3-D CFD studies were utilized to quickly screen two bowl concepts and assess their sensitivities to a few of the other parameters. The two most promising bowl concepts were built into single-cylinder engines for optimization of the rest of the combustion system parameters. 1-D CFD models were used to set boundary conditions at intake valve closure for 3-D CFD which was used for the closed-cycle portion of the simulation.

The development of an integrated Perforated Manifold, Muffler, and Catalyst (PMMC) for an automotive engine exhaust system is described. The design aims to reduce tailpipe emissions and improve engine power while maintaining low sound output levels from the exhaust. The initial design, based on simplified acoustic and fluid dynamic considerations, is further refined through the use of a computational approach and bench tests. A final prototype is fabricated and evaluated using fired engine dynamometer experiments. The results confirm earlier analytical estimates for improved engine power and reductions of emissions and noise levels.

Several types of hybrid-electric vehicles have been developed at Ford Research Laboratory. Among the parallel hybrid systems with a single electric motor, two types were studied. In the first type, the electric motor was attached directly to the crankshaft (mild hybrid) [1], to enable the engine start-stop and regeneration functions. In the second type (full hybrid) the electric motor was connected to the engine through the use of a clutch to allow electric launch of the vehicle and pure electric driving at low speeds. The full hybrid powertrain described in this paper uses a more powerful electric motor for enhanced regenerative braking and engine power assist. An engine-disconnecting clutch saves energy during both the electric propulsion and during vehicle braking. When the clutch is disengaged the engine is shut-off, which eliminates the energy otherwise spent on motoring the engine during electric propulsion.

An experimental data base of catalyst conversion efficiency was generated, using a tubular flow reactor which contained either a Pt/Rh (5:1; 40g/ft3) or a Pd/Rh (5:1; 40g/ft3) catalyst sample, for the purpose of updating the kinetic rate constants in the Ford TWC model. Steady-state conversion efficiency of CO, NO, C3H8, C3H6, H2 and O2 through these catalysts were determined for a variety of inlet species concentrations and inlet gas temperatures. These data were obtained for values of redox ratio between 0.5 (excess O2) and 4.0, and inlet gas temperatures between 371°C and 593°C. All experimental details and modeling procedures utilized in obtaining an optimized set of kinetic parameters are included. Results of these experiments show significant improvement in CO and NO conversion efficiency and an increase in NH3 production for both catalyst formulations over previous generation catalyst formulations when redox ratio is greater than unity.