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As part of an ongoing technical collaboration between Ford and Rouge Steel Company, a comprehensive study of door slam event was undertaken. The experimental phase of the project involved measurements of accelerations at eight locations on the outer panel and strains on six locations of the inner panel. Although slam tests were conducted with window up and window down, results of only one test is presented in this paper. The CAE phase of the project involved the development of suitable “math” model of the door assembly and analysis methodology to capture the dynamics of the event. The predictability of the CAE method is examined through detailed comparison of accelerations and strains. While excellent agreement between CAE and test results of accelerations on the outer panel is obtained, the analysis predicts higher strains on the inner panel than the test. In addition, the tendency of outer panel to elastically buckle is examined.

A methodology for predicting the fatigue initiation life in metals experiencing multiaxial non-proportional loading is presented. The methodology utilizes nonlinear finite-element analysis to determine the stress distribution of the loaded component. This distribution is used in conjunction with a physically based damage law to determine the cycles to failure. The damage law is based on the fatigue prediction method introduced by Dang Van [1], and further developed by Papadopoulos [2] and Morel [3]. The fatigue damage initiation is treated as the persistent crystalline slip phenomenon taking place on the order of a grain or few grains. The damage variable is chosen to be the accumulated plastic strain at this scale. The initiation life is determined when the damage variable reaches a critical value. The developed methodology is applicable to both in-phase and out-of-phase loading, without any empirical adjustment parameter.

The Magma engine concept is characterised by a high compression ratio, central injector combustion system employed in a downsized direct-injection gasoline engine. An advanced boosting system and Miller cycle intake-valve closing strategies are used to control combustion knock while maintaining specific performance. A key feature of the Magma concept is the use of high CR without compromise to mainstream full-load performance levels. This paper focuses on development of the Magma combustion system using a single-cylinder engine, including valve event, air motion and injection strategies. Key findings are that Early Intake Valve Closing (EIVC) is effective both in mitigating knock and improving fuel consumption. A Net Indicated Mean Effective Pressure (NIMEP) equivalent to 23.6 bar Brake Mean Effective Pressure (BMEP) on a multi-cylinder engine has been achieved with a geometric compression ratio of 13:1.

Powertrain mounts are one of the important design characteristics of a vehicle. Powertrain is mostly mounted to the front subframe and once installed in a vehicle, powertrain mounting has an important role in determining the vehicle vibration characteristics. A good mounting system isolates engine input vibration from the vehicle body and minimizes the effect of road inputs to the customer. This paper discusses results of several dynamic models as they relate to noise, vibration and harshness (NVH) and compares the accuracy of these models. Various powertrain models are studied and their accuracy in comparison with full a vehicle model is discussed.

Future fuel economy targets represent a significant challenge to the automotive industry. While a range of technologies are in research and development to address this challenge, they all bring additional cost and complexity to future products. The most cost effective solutions are likely to be combinations of technologies that in isolation might have limited advantages but in a systems approach can offer complementary benefits. This presentation describes work carried out at Ricardo to explore Intelligent Electrification and the use of Stratified Charge Lean Combustion in a spark ignition engine. This includes a next generation Spray Guided Direct Injection SI engine combustion system operating robustly with highly stratified dilute mixtures and capable of close to 40% thermal efficiency with very low engine-out NOx emissions.

Internal combustion engine noise and vibration are major issues for car makers, and these are even more important for High-Level Pick-ups and SUV's which applies modern diesel engines. One important player in this scenario is the second-order unbalanced forces vibration produced by the conventional in-line 4-cylinder engine configurations, which leads to high-frequency excitation of vehicle's structure and consequent internal noise. This paper studies a balancer shaft solution for the mentioned engine configuration, as well as major design alternatives and development process and issues. This paper also presents an example of a balancer shaft design and development for a high speed diesel engine, as well as proposes a design/decision matrix methodology. Such methodology, which can be applied to any design or engineering case, helps design engineers make the right decision amongst different options by using a very simple and objective matrix.

Heavy fuel engines have typically been limited to large, heavy compression ignition engines. However, with the push by the US military to use a common fuel (JP5/JP8/diesel) there is a need to develop small, lightweight, high performance engines that are also capable of operating on heavy fuel. Recent advancements in air assisted direct injection technologies have improved fuel atomization to the level necessary to overcome the poor physical properties of heavy fuel. This has permitted the operation of small two-stroke engines which retain the advantage of a lightweight design with high power output. This paper discusses the process of benchmarking a two-stroke heavy fuel spark ignited engine with an integrated air-assist direct injection system. The setup and commissioning phases of the testing are outlined, including specific techniques for quantifying scavenging, burn rate, and heat release characteristics with the objective of validating a 1-D performance simulation model.

The growing competition of the automotive market makes more and more necessary the reduction of development time and consequently, the increase of the capacity to quickly respond to the launching of the competitors. One of the most costly phases on the vehicle development process is the field durability test, both in function of the number of prototypes employed and the time needed to its execution. More and more diffused, the fatigue life prediction methods have played an important part in the durability analysis via CAE. Nevertheless, in order they can be reliable and really being able to reduce the development time and cost, they need to be provided with load cases that can accurately represent the field durability tests. This work presents a CAE approach used for light trucks in order to get a reasonable understanding of component durability behavior due to payload increase. In general, road load data is not available for a new payload condition.

The U.S. Environmental Protection Agency, U.S. Department of Transportation's National Highway and Traffic Safety Administration, and the California Air Resources Board have recently released proposed new regulations for greenhouse gas emissions and fuel economy for light-duty vehicles and trucks in model years 2017-2025. These proposed regulations intend to significantly reduce greenhouse gas emissions and increase fleet fuel economy from current levels. At the fleet level, these rules the proposed regulations represent a 50% reduction in greenhouse gas emissions by new vehicles in 2025 compared to current fleet levels. At the same time, global growth, especially in developing economies, should continue to drive demand for crude oil and may lead to further fuel price increases. Both of these trends will therefore require light duty vehicles (LDV) to significantly improve their greenhouse gas emissions over the next 5-15 years to meet regulatory requirements and customer demand.

Combustion feedback using cylinder pressure sensors, ion current sensors or alternative sensing techniques is actively under investigation by the automotive industry to meet future legislative emissions requirements. One of the drawbacks of many rapid prototyping engine management systems is their available analog interfaces, often limited to 10-12 bits with limited bandwidth, sampling rate and very simple anti-aliasing filters. Processing cylinder pressure or other combustion feedback sensors requires higher precision, wider bandwidths and more processing power than is typically available. For these reasons, Ricardo in collaboration with GM Research has developed a custom, high precision analog input subsystem for the rCube rapid prototyping control system that is specifically targeted at development of combustion feedback control systems.

In internal combustion engines, liquid fuel injection is one of the most prevalent means of fuel delivery and air-fuel mixture preparation. The behavior of the fuel spray and wall film is a key factor in determining air-fuel mixing and hence combustion and emissions. A comprehensive model for the liquid fuel spray has been developed in conjunction with the one-dimensional gas flow code WAVE. The model includes droplet dynamics and evaporation, spray-wall impingement, wall film dynamics and evaporation. The fuel injector can be placed in the manifold, inlet port or cylinder. Liquid fuel droplets are injected with a prescribed size distribution, and their subsequent movement and vaporization are modeled via the discrete particle approach, frequently used in multi-dimensional CFD codes. This approach ensures conservation of mass, momentum and energy between the gas and liquid phases.

The Fischer-Tropsch (FT) process can be used to synthesize diesel fuels from a variety of energy sources, including coal, natural gas and biomass. Diesel fuels produced from the FT process are essentially sulfur-free, have very low aromatic content, and have excellent ignition characteristics. Because of these favorable attributes, FT diesel fuels may offer environmental benefits over transportation fuels derived from crude oil. Previous tests have shown that FT diesel fuel can be used in unmodified engines and have been shown to lower regulated emissions. Whereas exhaust emissions reductions from these previous studies have been impressive, this paper demonstrates that far greater exhaust emissions reductions are possible if the diesel engine is optimized to exploit the properties of the FT fuels. A Power Stroke 7.3 liter turbocharged diesel engine has been modified for use with FT diesel.

The Ethanol-Boosted Direct Injection (EBDI) demonstrator engine is a collaborative project led by Ricardo targeted at reducing the fuel consumption of a spark-ignited engine. This paper describes the design challenges to upgrade an existing engine architecture and the synergistic use of a combination of technologies that allows a significant reduction in fuel consumption and CO₂ emissions. Features include an extremely reduced displacement for the target vehicle, 180 bar cylinder pressure capability, cooled exhaust gas recirculation, advanced boosting concepts and direct injection. Precise harmonization of these individual technologies and control algorithms provide optimized operation on gasoline of varying octane and ethanol content.

As specific engine power output increases so does the heat rejected to the coolant. The resulting need to increase radiator size is counter-productive due to the lack of package space, and a strong desire to reduce, not increase, vehicle drag. Current tendency is to size the radiator to reject sufficient heat at extreme operating conditions (full engine power, high ambient). However, this “oversized” cooling system may only be needed by a small number of vehicles. A better approach could be to size the radiator for the majority, but not all, operational conditions and manage the coolant temperature by actively controlling coolant flow and engine output. This will need to be done without compromising durability or driveability. This approach sounds highly beneficial in principle, but how sound would it be in practice ? The authors have investigated the feasibility of active control by considering the details of radiator performance and engine heat rejection.

Due to the recent drive to reduce CO₂ emissions, the turbocharged direct injection spark ignition (turbo DISI) gasoline engine has become increasingly popular. In addition, future turbo DISI engines could incorporate a form of charge dilution (e.g., lean operation or external EGR) to further increase fuel efficiency. Thus, the conditions experienced by the fuel before and during combustion are and will continue to be different from those experienced in naturally aspirated SI engines. This work investigates the effects of fuel properties on a modern and prototype turbo DISI engine, with particular focus on the octane appetite: How relevant are RON and MON in predicting a fuel's anti-knock performance in these modern/future engines? It is found that fuels with high RON and low MON values perform the best, suggesting the current MON requirements in fuel specifications could actually be detrimental.

A finite element methodology, based on implicit numerical integration procedure, for simulating oil-canning tests on Door assemblies is presented. The method takes into account nonlinearities due to geometry, material and contact between parts during deformation. The simulation results are compared with experimental observations. Excellent correlation between experimental observations and analytical predictions are obtained in these tests. Armed with the confidence in the methodology, simulations on a door assembly are conducted to study the gage and grade sensitivities of the outer panel. The sensitivity studies are conducted on three different grades of steel for the outer panel. Further studies are conducted to understand the effects of manufacturing (forming operation) on the oil canning behavior of door assembly. Results demonstrate the utility of the method in material selection during pre-program design of automotive structures.

OEMs are investigating opportunities to reduce vehicle mass, driven by a need to meet upcoming CAFE targets, increase the range and reduce battery size of EVs. A number of lightweight materials including high strength steels, aluminum alloys, plastics and composites are now in production. To facilitate development of corporate R&D and commercialization plans for new materials, it is beneficial to understand the current manufacturing costs for production components, and their impact on piece price at different volumes. This paper investigates design and cost impact of light-weighting with respect to front door and floor assembly of Toyota Corolla and BMW i3. Toyota Corolla has a traditional steel body and is sold in high volumes while BMW i3 has relatively low annual sales and is primarily made of composite, aluminum and plastic parts.

This paper describes the features and capabilities of a comprehensive yet flexible computational tool ORBIT developed for analyzing journal bearings (e.g. connecting rod bearings and crankshaft bearings) in internal combustion engines. Several techniques for solving the hydrodynamic Reynolds Equation have been developed within this methodology which can be used appropriately by bearing designers/analysts depending on the level of detail required. Besides ideal circular bearings, this simulation tool also enables the analyst to consider the influence of a) non-circular journal bearing geometry, b) oil-feed holes/grooves, c) surface roughness, d) journal misalignment, e) rise in oil temperature and f) bearing elasticity effects (EHL) on bearing performance. The capabilities of the simulation code are demonstrated through a series of validation and case studies.

Acoustics of automotive intake and exhaust systems have been modelled very successfully for many years using 1D gas dynamic simulations. These use pseudo 3D models to allow complex components to be constructed from simple building blocks. In recent years, tools have appeared that automate the construction of network models from 3D geometries of intake and exhaust components. Using these tools, concurrent noise and performance predictions are a core part of most engine development programmes. However, there is still much interest in the more traditional field of linear acoustics: analysing the acoustic behaviour of isolated components or predicting radiated noise using a linear source. Existing approaches break the intake and exhaust system down into a set of components, each with known acoustic properties. They are then connected together to create a network that replicates the donor non-linear model.

Worldwide, Fuel Economy (FE) legislation increasingly influences vehicle and engine design, and drives friction reduction. The link between lubricant formulation and mechanical friction is complex and depends on engine component design and test cycle. This Motored Friction Tear Down (MFTD) study characterizes the friction within a 3.6L V6 engine under operating conditions and lubricant choices relevant to the legislated FE cycles. The high-fidelity MFTD results presented indicate that the engine is a low-friction engine tolerant of low viscosity oils. Experiments spanned four groups of engine hardware (reciprocating, crankshaft, valvetrain, oil pump), five lubricants (four candidates referenced against an SAE 0W-20) and five temperature regimes. The candidate lubricants explored the impact of base oil viscosity, viscosity modifier (VM) and friction modifier (FM) content.