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Electronics components are estimated to be between 9 to 15 % of a total vehicle cost, and this trend will remain strong for the next years. The amount of electronics content in a vehicle has grown steadily since 1970's, and as a result, development challenges such as testing and validation are a key aspect of its overall development costs. Testing costs can amount easily to US$ 500 k in medium complex automotive parts of a vehicle (e.g. instrument cluster) depending on a specific OEM customer demand, and this on top of limited regional laboratory capacity can also lead to increased testing time. The goal of this paper is to outline key aspects of electronics in vehicle components testing, including overall costs and timing, and propose a lean approach to optimize such costs & timing. The key aspects of such optimization include not only resources, but also laboratories and upfront OEM customer planning.

Accurate evaluation of vehicles' transient total power requirement helps achieving further improvements in vehicle fuel efficiency. When operated, the air-conditioning (A/C) system is the largest auxiliary load on a vehicle, therefore accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation models, such as "Autonomie," have been used by OEMs to evaluate vehicles' energy performance. However, the load from the A/C system on the engine or on the energy storage system has not always been modeled in sufficient detail. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software MATLAB/Simulink® is frequently used by vehicle controls engineers to develop new and more efficient vehicle energy system controls.

A D.C. permanent magnet motor powered fan can serve as a cooling package air flow meter. This allows for continuous air flow monitoring during vehicle operation with applications to more precise air flow control schemes. In the freewheel mode, the air flow is a linear function of the open circuit voltage of the motor. In the powered mode, the motor voltage and current can be used with a motor and fan model to predict fan air flow. The model is explained and verifying test results are presented. Comparison of the accuracy and complexity vs. that of arrays of precision anemometers is provided.

Spot Welding is an important welding technique which is widely used in automotive and aerospace industry. One of the keys of checking the quality of the welds is measuring the size of the nugget. In this paper, the Shearographic technique is utilized to test weld joint samples under the thermal loading condition. The goal is to identify the different group of the nuggets (i.e. small, middle, and large sizes, which indicate the quality of spot welds). In the experiments, the sample under test is fixed by a magnet method from behind at the four edges. Thermal loading was applied in the back side and the sample is inspected using the digital Shearographic system in the front side. Results show the great possibility of classifying the nugget size into three groups and the measurement is well repeatable.

This paper discusses steps for identifying, evaluating and recommending a quantifiable design metric or metrics for Side Airbag (SAB) development. Three functionally related and desirable attributes of a SAB are assumed at the onset, namely, effective SAB coverage, load distribution and efficient energy management at a controlled force level. The third attribute however contradicts the “banana shaped” force-displacement response that characterizes the ineffective energy management reality of most production SAB. In this study, an estimated ATD to SAB interaction energy is used to size and recommend desired force-deformation characteristic of a robust energy management SAB. The study was conducted in the following three phases and corresponding objectives: Phase 1 is a SAB assessment metric identification and estimation, using a uniform block attached to a horizontal impact machine.

This study investigates the autoignition of Primary Reference Fuels (PRFs) using a detailed kinetic model. The chemical kinetics software CHEMKIN is used to facilitate solutions in a constant volume reactor and a variable volume reactor, with the latter representing an IC engine. Experimental shock tube and HCCI engine data from literature is compared with the present predictions in these two reactors. The model is then used to conduct a parametric study in the constant volume reactor of the effect of inlet pressure, inlet temperature, octane number, fuel/air equivalence ratio, and exhaust gas recirculation (EGR) on the autoignition of PRF/air mixtures. A number of interesting characteristics are demonstrated in the parametric study. In particular, it is observed that PRFs can exhibit single or two stage ignition depending on the inlet temperature. The total ignition delay, whether single or two stage, is correlated withn-C7H16/O2 ratio.

Powertrain noise is a significant factor in determination of the overall vehicle refinement expected by today's discriminating automotive customer. Development of a powertrain to meet these expectations requires a thorough understanding of the contributing noise sources. Specifically, combustion noise greatly impacts the perception of sound levels and quality. The relevance of combustion noise development has increased with the advent of newer efficiency-driven technologies such as direct injection or homogeneous charge compression ignition. This paper discusses the application of a CSL (Combustion Sound Level) analysis-a method for the identification and optimization of combustion noise. Using CSL, it is possible to separate mechanical and combustion noise sources.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

A correlation study was performed between static wind tunnel testing and computational fluid dynamics (CFD) for a small hatchback vehicle, with the intent of evaluating a variety of different wheel and tire designs for aerodynamic forces. This was the first step of a broader study to develop a tool for assessing wheel and tire designs with real world (rolling road) conditions. It was discovered that better correlation could be achieved when actual tire scan data was used versus traditional smooth (CAD) tire geometry. This paper details the process involved in achieving the best correlation of the CFD prediction with experimental results, and describes the steps taken to include the most accurate geometry possible, including photogrammetry scans of an actual tire that was tested, and the level of meshing detail utilized to capture the fluid effects of the tire detail.

A fundamental problem in the development of automotive thermal protection strategies is the understanding of the effect of time and temperature on vehicle components life and their performance throughout the life of the vehicle. Due to restrictions on emissions and the stringent requirements for improved fuel economy, the use of polymers and synthetic materials has been widely adopted in automotive applications. It is therefore critical to develop a process to estimate life of engineering materials based on thermal testing and material physical properties. While a series of carefully selected vehicle tests can determine components temperatures during different testing conditions, a need still exists to determine the expected component life and performance throughout the life of the vehicle. Kinetic models have been widely used, in literature, to determine the aging of polymeric and composite materials over time.

An investigation into the design, development and evaluation of a “new” washcoat technology family that enables significant reductions in rhodium usage levels has been concluded. These findings were demonstrated on three vehicle applications utilizing different calibration A/F control strategies. Additional testing investigated optimal Rh placement on a two brick catalyst system and the impact on FTP and US-06 test cycles. This study concludes with an evaluation of full useful life aged catalysts tested on 6 and 8 cylinder applications that are shown to have met Bin 4 FFV and ULEVII emission standards.

An experiment was conducted testing a powertrain package consisting of a four cylinder four valve engine coupled to a four speed automatic transmission in a dynamometer test cell. Cylinder pressure transducers, an encoder, and other instrumentation were used to measure transient combustion events. The transient cycle chosen for testing was a Cold 80 of the Federal Test Procedure (FTP) that produces a standardized fuel economy value. After analyzing the combustion events, a determination was made between the spark advance delivered and a revised spark advance for optimum combustion efficiency. Based upon the relationship between spark advance and fuel consumption, a prediction for the improved fuel consumption was made. The testing was then repeated to evaluate the revised spark advance and the fuel economy benefits in comparison to the predicted values.

This paper focuses on the numerical investigation of the mixing and combustion of ethanol and gasoline in a single-cylinder 3-valve direct-injection spark-ignition engine. The numerical simulations are conducted with the KIVA code with global reaction models. However, an ignition delay model mitigates some of the deficiencies of the global one-step reaction model and is implemented via a two-dimensional look-up table, which was created using available detailed kinetics models. Simulations demonstrate the problems faced by ethanol operated engines and indicate that some of the strategies used for emission control and downsizing of gasoline engines can be employed for enhancing the combustion efficiency of ethanol operated engines.

Because combustion engine equipped vehicles must conform to stringent hydrocarbon (HC) emission requirements, many of them on the road today are equipped with an engine air intake system that utilizes a hydrocarbon adsorber. Also known as HC traps, these devices capture environmentally dangerous gasoline vapors before they can enter the atmosphere. A majority of these adsorbers use activated carbon as it is cost effective and has excellent adsorption characteristics. Many of the procedures for evaluating the adsorbtive performance of these emissions devices use mass gain as the measurand. It is well known that activated carbon also has an affinity for water vapor; therefore it is useful to understand how well humidity must be controlled in a laboratory environment. This paper outlines investigations that were conducted to study how relative humidity levels affect an activated carbon hydrocarbon adsorber.

This paper will describe the development of the 3-load cell tumble meter. This is a new method for measuring the tumble component of in-cylinder mixture motion. In-cylinder mixture motion is an important parameter for understanding and improving combustion stability of piston engines.

This paper gives an overview of a scalable engine management system architecture for motorcycle and other small engine based vehicle applications. The system can accommodate any engine sizes and up to four cylinders. The architecture incorporates advanced functionalities such as oxygen sensing, closed loop fueling, wall-wetting compensation, purge control, start & idle control and deceleration fuel cut-off. Additionally, a number of vehicle-related controls are integrated in the system. Diagnostic and safety related features have also been incorporated with limp-home capability. The software architecture is compatible with different hardware solutions. The system has been implemented in several OEM vehicles around the globe and meets EURO-3 emission requirements.

To obtain the maximum output power and fuel economy from an internal combustion engine, it is often necessary to detect engine knock and operate the engine at its knock limit. This paper presents the ability to detect knock using in-cylinder ionization signals on a large displacement, air-cooled, “V” twin motorcycle engine over the engine operational map. The knock detection ability of three different sensors is compared: production knock (accelerometer) sensor, in-cylinder pressure sensor, and ionization sensor. The test data shows that the ionization sensor is able to detect knock better than the production knock sensor when there is high mechanical noise present in the engine.

The requirement of reduced emissions and improved fuel economy led the introduction of direct-injection (DI) spark-ignited (SI) engines. Dual-fuel injection system (direct-injection and port-fuel-injection (PFI)) was also used to improve engine performance at high load and speed. Ethanol is one of the several alternative transportation fuels considered for replacing fossil fuels such as gasoline and diesel. Ethanol offers high octane quality but with lower energy density than fossil fuels. This paper presents the combustion characteristics of a single cylinder dual-fuel injection SI engine with the following fueling cases: a) gasoline for PFI and DI, b) PFI gasoline and DI ethanol, and c) PFI ethanol and DI gasoline. For this study, the DI fueling portion varied from 0 to 100 percentage of the total fueling over different engine operational conditions while the engine air-to-fuel ratio remained at a constant level.

Ethanol is widely used as a gasoline component to provide a prescribed amount of oxygenates and for its perceived advantages of less dependence on petroleum based products and lowering overall CO2 emissions. In most cases the level of ethanol in gasoline does not exceed 10%. In some parts of the Unites States, E85 fuel consisting of 85% ethanol and 15% gasoline is commonly available. Many US vehicles sold today are specially adapted for use of both gasoline and high ethanol fuels; so-called Flexible Fuel Vehicles (FFV). While high ethanol fuels are currently a small percentage of the overall gasoline pool, they provide an interesting opportunity to study the effects that ethanol use in gasoline may have on lubricant related performance. Based on past industry experience with methanol based fuel, theoretical areas of concern for ethanol based fuels are valve train rust and potential problems associated with high amounts of water in the lubricant.

The intake and exhaust port design plays a substantial role in performance of combustion systems. The port design determines the volumetric efficiency and in-cylinder charge motion of the spark-ignited engine which influences the thermodynamic properties directly related to the power output, emissions, fuel consumption and NVH properties. Thus intake port has to be appropriately designed to fulfill the required charge motion and high flow performance. While turbulence intensity and air-mixture quality affect dilution tolerance and fuel economy as a result, breathing ability affects wide open throttle performance. Traditional approaches require experimental techniques to reach a target balance between the charge motion and breathing capacity. Such techniques do not necessarily result in an optimized solution.