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This paper outlines the development process of a vibration isolation system for the timing chain guides of an internal combustion engine. It was determined through testing that the timing chain guides are a significant path by which the chain/sprocket impacts are transmitted to other powertrain components. These components radiate the energy as chain mesh order narrow band sound as well as wide band energy. It was found that isolation of the chain guides produced a significant reduction in radiated sound levels, reduced mesh frequency amplitudes, and improved sound quality. The development process utilized indirect force measurement techniques for simulation of the chain loading and FEA prediction of the resulting chain guide forces and displacements. The design of the isolation system involved material selection based on dynamic properties, frequency and temperature ranges, the operating environment, FEA geometry optimization, and durability testing.

There have been many articles published in the last decade or so concerning the components of an electronic stability control (ESC) system, as well as numerous statistical studies that attempt to predict the effectiveness of such systems relative to crash involvement. The literature however is free from papers that discuss how engineers might develop such systems in order to achieve desired steering, handling, and stability performance. This task is complicated by the fact that stability control systems are very complex and their designs and what they can do have changed considerably over the years. These systems also differ from manufacturer to manufacturer and from vehicle to vehicle in a given maker of automobiles. In terms of ESC hardware, differences can include all the components as well as the addition or absence of roll rate sensors or active steering gears to name a few.

Since doors are repeatedly used by vehicle owner, they have a great influence on his or her perception of vehicle quality. The door open overload is an abusive load requirement for customer usage. The doors must withstand loads which force the door open against its stop, leading to concern over the effects of permanent set to the functioning of the door system and the margins/ flushness. Traditionally, the CAE is utilized to objectively evaluate the deflections and permanent set at the door latch to evaluate door open overload requirement. In this study, the FEA methodology has been applied to expand the scope beyond traditional method to simulate door open overload condition. The change in the margin and flushness due to the permanent set are evaluated using nonlinear analysis (ABAQUS). The results show that the method helps designers to ensure the door meets the margin/flushness criteria for door open overload condition during early stage of the door design process.

Several studies have been conducted in an effort to bring Computational Fluid Dynamics (CFD) out of the research arena (5) and into the product design environment as a useful aerodynamic design tool. The focus of these studies has ranged from extremely simple shapes to more complex geometries representative of real vehicles. This paper presents the results of real vehicle applications in which CFD was used to predict the aerodynamic effect of proposed surface modifications. The simulation data was generated using a numerical method derived from lattice gas theory to evaluate the aerodynamic effect of surface modifications. The commercial software Powerflow was used to prepare the model, perform the simulation and post-process the results. These case studies were performed in parallel with real vehicle development programs. The depth of experimental comparison data was limited by traditional vehicle program timing and budget constraints.

A standard port fuel injected, unthrottled single cylinder four-stroke SI engine, with a compression ratio of 10.3:1, and using standard gasoline fuel, has been adapted to operate in the homogeneous charge compression ignition (HCCI) mode, by modifying the valve timing. It has been found that over a speed range of between 1300 and 2000 rpm, and lambda values of between 0.95 and 1.1, stable operation is achieved without spark ignition. The internal EGR rate was estimated to be about 60%, and emissions of NOX were typically 0.25 g/kWh. Practical implementation of this HCCI concept will require variable valve timing, which will also enable reversion to standard SI operation for maximum power.

The Multi Material Lightweight Vehicle (MMLV) developed by Magna International and Ford Motor Company is a result of a US Department of Energy project DE-EE0005574. The project demonstrates the lightweighting potential of a five passenger sedan, while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full vehicle testing was conducted. The Mach-I vehicle design, comprised of commercially available materials and production processes, achieved a 364kg (23.5%) full vehicle mass reduction, enabling the application of a 1.0-liter three-cylinder engine resulting in a significant environmental benefit and fuel reduction. This paper reviews the mass reduction and structural performance of aluminum, magnesium, and steel components for a lightweight multi material door design for a C/D segment passenger vehicle. Stiffness, durability, and crash requirements are assessed.

The Multi Material Lightweight Vehicle (MMLV), developed by Magna International and Ford Motor Company, is a result of US Department of Energy project DE-EE0005574. The project demonstrated the lightweighting potential of a five-passenger sedan while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full-vehicle testing was conducted. The Mach-I vehicle design, comprised of commercially-available materials and production processes, achieved a 364 kg (23.5%) full-vehicle mass reduction. This resulted in environmental benefits and fuel economy improvements. A significant factor in the overall MMLV mass reduction was the decrease in the powertrain system weight from 340 kg (conventional) to 267 kg (MMLV). This enabled the application of a 1.0-liter three-cylinder engine as the main powerplant. By downsizing the engine, and by implementing material changes within the engine, the weight of the dressed engine was lowered by 29 kg.

While weight reduction in automotive design and manufacturing has been on-going for several years, in the area of powertrain technology lightweighting has been a difficult challenge to overcome due to functional requirements, as well as material and manufacturing constraints. The Multi Material Lightweight Vehicle (MMLV) developed by Magna International and Ford Motor Company is a result of US Department of Energy project DE-EE0005574. The project demonstrates the lightweighting potential of a five passenger sedan, while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full vehicle testing was conducted. The Mach-I vehicle design, comprised of commercially available materials and production processes, achieved a 364kg (23.5%) full vehicle mass reduction, enabling the application of a 1.0-liter three-cylinder engine resulting in a significant environmental benefit and fuel reduction.

This paper details the lightweighting efforts of the Ford Research & Advanced Transmission team as part of the Multi Material Lightweight Vehicle Project. The Multi Material Lightweight Vehicle (MMLV) developed by Magna International and Ford Motor Company is a result of a US Department of Energy project DE-EE0005574. The project demonstrates the lightweighting potential of a five passenger sedan, while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full vehicle testing was conducted. The Mach-I vehicle design, comprised of commercially available materials and production processes, achieved a 364kg (23.5%) full vehicle mass reduction, enabling the application of a 1.0-liter three cylinder engine resulting in a significant environmental benefits and fuel consumption reduction.

The exhaust blowdown pulse from each cylinder of a multi-cylinder engine propagates through the exhaust manifold and can affect the in-cylinder pressure of other cylinders which have open exhaust valves. Depending on the firing interval between cylinders connected to the same exhaust manifold, this blowdown interference can affect the exhaust stroke pumping work and the exhaust pressure during overlap, which in turn affects the residual fraction in those cylinders. These blowdown interference effects are much greater for a turbocharged engine than for one which is naturally aspirated because the volume of the exhaust manifolds is minimized to improve turbocharger transient response and because the turbines restrict the flow out of the manifolds. The uneven firing order (intervals of 90°-180°-270°-180°) on each bank of a 90° V8 engine causes the blowdown interference effects to vary dramatically between cylinders.

The objective was to engineer a world-class supercar body that faithfully reproduces the 2002 Concept and pays homage to the 1960's road racer. The car had to be designed, developed and launched in 24 months, while meeting tough requirements for function, weight, occupant package and aerodynamics. Challenging features such as the cantilevered door, “clamshell” engine decklid and a deeply contoured hood were to be included. This paper will discuss how a dedicated team of enthusiasts can have a flexible approach to the engineering process, material selections and manufacturing processes to achieve the designer's vision in 24 months (Figure 1).

The recent trends of increasing driveline torque and use of traction control devices call for increasingly higher durability capacity from driveline components. Bench and vehicle durability tests are often used to validate designs, but they are not cost-effective and take months to complete. Traditional finite element analysis (FEA) procedures have been used effectively in the re-design of driveline components to reduce stress, and occasionally, to predict fatigue life. But in the case of certain rotating components, such as the Axle Differential Case, where the component sees large stress/strain fluctuations within the course of one complete rotation, even under constant input torque, historical fatigue analysis (when conducted) yields very conservative results. The axle differential case tends to be one of the weakest links in the rear axle assembly. Therefore, there is a crucial need for analytical methods to more accurately predict fatigue life to reduce testing time and cost.

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.