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The paper presents a model-based approach to testing embedded automotive software systems in a real-time. Model-based testing approach relates to a process of creating test artifacts using various kinds of models. Real-time testing involves the use of a real-time environment to implement test application. Engineers shall use real-time testing techniques to achieve greater reliability and/or determinism in a test system. The paper contains an instruction how to achieve these objectives by proper definition, implementation, execution, and evaluation of test cases. The test cases are defined and implemented in a modeling environment. The execution and evaluation of test results is made in a real-time machine. The paper is concluded with results obtained from the initial deployment of the approach on a large scale in production stream projects.

The presentation describes a technical solution for 100 Mbit/s Ethernet Data transmission cabling. This solution considers the specific requirements of automotive wiring harness and manufacturing. It bases on standard automotive connectors and headers. Currently the development of automotive electronic architecture considers central ECU or data backbone structure for the upcoming EE architecture (e. g. single ECU for network; SEN). For these structures solid and cost effective data backbone solutions are essential. Ethernet, a wide distributed and well-known bus system for office and industry data distribution provide a wide range of software tools and many physical layer solutions. Several cabling systems are available. Based on this we propose a solution for automotive application.

As fuel prices continue to rise automotive manufacturers continue to push their suppliers to provide technology that improves the potential fuel efficiency of their applications. In addition there is an increasing trend towards smaller, lighter and more compact vehicles to mitigate the automotive carbon footprint. These movements necessitated the development of a new compact, low mass, variable displacement compressor to match the requirements for these smaller and more efficient vehicles. The new Delphi MVC, or Miniature Variable Compressor, meets these requirements by integrating the high efficiency of our latest swashplate variable compressor design into a compact and lightweight package. This design can be offered in a range of displacements from 80 to 100cc and can be offered as either internally or externally controlled to support the customer's needs.

This paper discusses the effect of the field stress variance on the value of demonstrated reliability in the automotive testing. In many cases the acceleration factor for a reliability demonstration test is calculated based on a high percentile automotive stress level, typically corresponding to severe user or environmental conditions. In those cases the actual field (‘true’) reliability for the population will be higher than that demonstrated by a validation test. This paper presents an analytical approach to estimating ‘true’ field reliability based on the acceleration model and stress variable distribution over the vehicle population. The method is illustrated by an example of automotive electronics reliability demonstration testing.

The progressive trend towards the GDi engine downsizing, the focus on better fuel efficiency and performance, and the regulatory requirements with respect to the combustion emissions have brought the focus of attention on strategies for improvement of in-cylinder mixture preparation and identification and elimination of the sources of combustion emissions, in particular the in-cylinder particulate formation. This paper discusses the fuel system components, injector dynamics, spray characteristics and the single cylinder engine combustion investigation of a 40 [MPa] capable conventional GDi inwardly-opening multi-hole fuel injection system. It provides results of a study of the influence of fuel system pressure increase between 5 [MPa] to 40 [MPa], in conjunction with the injector static flow and spray pattern, on the combustion characteristics, specifically the particulate and gaseous emissions and the fuel economy.

In previous work, Gasoline Direct Injection Compression Ignition (GDCI) has demonstrated good potential for high fuel efficiency, low NOx, and low PM over the speed-load range using RON91 gasoline. In the current work, a four-cylinder, 1.8L engine was designed and built based on extensive simulations and single-cylinder engine tests. The engine features a pent roof combustion chamber, central-mounted injector, 15:1 compression ratio, and zero swirl and squish. A new piston was developed and matched with the injection system. The fuel injection, valvetrain, and boost systems were key technology enablers. Engine dynamometer tests were conducted at idle, part-load, and full-load operating conditions. For all operating conditions, the engine was operated with partially premixed compression ignition without mode switching or diffusion controlled combustion.

The focus of this study is investigation of the influence of fuel system pressure, intake tumble charge motion and injector seat specification - namely the static flow and the plume pattern - on the GDi engine particulate emissions under the homogenous combustion operation. The paper presents the spray characteristics and the single cylinder engine combustion data for the Delphi Multec® 14 GDi multi-hole fuel injector, capable of 40 [MPa] fuel system pressure. It provides results of a study of the influence of fuel pressure increase between 5 [MPa] to 40 [MPa], for three alternative seat designs, on the combustion characteristics, specifically the particulate and gaseous emissions and the fuel consumption. In conjunction with the fuel system pressure, the effect of enhanced charge motion on the combustion characteristics is investigated.

This paper presents results of a coupling of the Volume-of-Fluid Large-Eddy simulation (VOF-LES) of the jet primary breakup with a Lagrangian stochastic spray simulation of a GDi multi-hole injector. The objective is to assess the potential of replacing the phenomenological models of jet primary atomization with the stochastic parcel size - velocity data extracted from the VOF-LES analysis. The paper describes the methodology and assesses the predictive capability achieved, through comparison of the Lagrangian far-field spray simulation results with the complete experimental spray characterization data under the atmospheric ambient conditions. The injector sac-nozzle flow and jet primary breakup simulation is performed with the Open-FOAM code. The simulation of the spray development processes - of propagation, evaporation and secondary atomization - is performed with the AVL-FIRE commercial CFD code adopting the standard Lagrangian discrete droplet method.

Most current automotive and light truck fuel level sensors are essentially rotary potentiometers that have been designed to survive the chemically harsh environments found in the fuel tank. This paper will chronicle the design improvements made from the early wire wound versions to today's more robust thick film ink systems. The paper will highlight potential failure modes and discuss techniques to reduce noise and increase wear life. Data will be provided regarding changes in the circuit layout, ink compositions, and contact materials. Special consideration will be given to the adverse effects associated with the reactive sulfur prevalent in today's fuels.

Over the past 20 years automobile quality, and consumer perceptions thereof, have been an increasing part of the vehicle engineering process. In automotive systems, torque-induced handwheel vibration is a significant source of consumer annoyance. When dealing with torque recordings containing a single or very small number of sinusoids, a time-referenced signal can easily be manipulated to yield instantaneous torque estimates. As the number of sinusoids (orders) grows, however, this becomes more difficult. In this paper, the authors demonstrate a simple technique to effectively estimate instantaneous torque level of high-order torque components when there are many higher-order sinusoids. The point is made that basic signal processing techniques applicable to time-referenced signals are also applicable to those referenced to angle or other variables.

Most current flex-fuel vehicles are capable of operating on gasoline/ethanol blends from E0 to E85. The presence of gasoline in the fuel enables cold startability because some of its more volatile components can still vaporize at cold temperatures and produce an ignitable mixture. However when E100 is used, other means are required for cold starting because of ethanol's relatively low vapor pressure at low temperatures. A common technique is to employ an auxiliary gasoline fuel system for use only when temperatures are too low for the vehicle to start on E100 alone. But the added cost, complexity and maintenance of such systems have driven the search for a simpler approach. One such technique is to heat the fuel prior to injection. Fuel systems currently exist where heating occurs within the main conduit of the fuel rail. Another method is to heat the fuel within each fuel injector.

As automotive and commercial vehicle OEM's continue their quest to reduce cost, product selection, quality, and reliability must be maintained. On-engine and wheel located connection systems create the greatest challenges due to the extreme levels of vibration. In the past, devices were fewer, and there where less direct connects in high vibration locations (Engine/ wheel sensors, electronic controllers, fuel injectors). Instead, small wire harnesses (“pigtails”) were commonly used. These pigtails can dampen the effect of the environment which includes mild to severe vibration by keeping the environmental effect away from the electrical connection contact point. Electrically connecting directly to the device creates new challenges in the connection system with the increased threat of fretting corrosion. Suppliers supporting OEM's are attempting to meet these direct connect requirements with lubrication, precious metal plating, and high contact force contacts.

Fuel systems associated with Gasoline Direct Injection (GDi) engines operate at pressures significantly higher than Port Fuel Injection (PFI) engine fuel systems. Because of these higher pressures, GDi fuel systems require a high pressure fuel pump in addition to the conventional fuel tank lift pump. Such pumps deliver fuel at high pressure to the injectors multiple times per engine cycle. With this extra hardware and repetitive pressurization events, vehicles equipped with GDi fuel systems typically emit higher levels of audible noise than those equipped with PFI fuel systems. A common technique employed to cope with pump noise is to cover or encase the pump in an acoustic insulator, however this method does not address the root causes of the noise. To contend with the consumer complaint of GDi system noise, Delphi and Magneti Marelli have jointly developed a high pressure fuel pump with reduced audible output by concentrating on sources of noise generation within the pump itself.

Thinwall substrates used in modern catalytic converters are more sensitive to assembly and operating forces. Various converter assembly processes are characterized using real time force transducer technology. The force distribution data from these assembly methods are presented. The analysis of this data leads to recommendations for packaging of converters depending on catalyst strength.

Close coupled catalysts and new ceramic catalyst substrates have significantly improved the light-off performance of automotive converters required to meet stringent emission requirements. The hotter environment of these catalytic converters and the lower structural strength of the ceramic substrates require the rethinking of converter designs. The development of new package requirements to accommodate the change in environment and new substrates are discussed. A historical perspective on converter durability is presented as reference. Development of durability test protocols is essential to verifying product durability performance to these new environments. Data collection and documentation of testing templates are shown to demonstrate the effectiveness of tests that represent real world environments. Design improvements to address failure modes are discussed along with durability improvement results.

A majority of the plastics manufacturing operations are dependent on the formability of the molten thermoplastics. Ability of the material to flow at a set temperature influences the formability and the overall polymer melt process. Lubricating additive technologies are being developed to engineer the melt flow performance of the resin, promoting the compounding and molding process such as to reduce torque on the motor, reduced shear degradations, enhance uniform filling of hard-to-fill section, promoting thin wall molding, and influence the overall cycle time. Various lubricants are used in formulations to supplement superior flow and metal release with minimal effect on mechanical properties. This paper discusses the methodology to characterize the effectiveness of melt flow additives through comparing two different processing aids in Polybutylene terephthalate (PBT) polyester filled and unfilled matrix and imply differences in processing.

This study is concerned with quantitative analysis of the primary atomization, regarding the droplet size-velocity distribution function, of a multi-hole GDi plume through application of the Volume-of-Fluid Large Eddy Simulation (VOF-LES) method. The distinguishing feature of this study is the inclusion of an accurate seat /nozzle flow domain into the simulation. A VOF-LES study of the seat-nozzle flow and the near-field primary atomization of a single plume of a GDi multi-hole seat is performed. The geometry pertains to a purpose-built 3-hole GDi seat with three identical flow hole and counter-bore nozzles, arranged with 120° circumferential spacing. The VOF-LES prediction of the jet primary breakup structure and near-field macroscale is compared with spray imaging data. The droplet size and velocity distributions within a 4mm vicinity of the nozzle are analyzed. The results show production of a wide droplet size distribution through the jet primary atomization.

After the second worldwide oil crisis, Brazil put in place by 1975 a strategic plan to stimulate the usage of ethanol (from sugar cane), to be mixed to the gasoline or to be sold as 100% ethanol fuel (known as E100). To enable an engine to operate with both gasoline and ethanol (and their mixtures), by 2003 the “Flex Fuel” technology was implemented. By 2012 calendar year, from a total of about 3.8 million vehicles sold in the Brazilian market, 91% offered the “Flex Fuel” technology, and great majority used a gasoline sub-tank to assist on cold starts (typically below 15°C, where more than 85% of ethanol is present in fuel tank). The gasoline sub-tank system suffers from issues such as gasoline deterioration, crash-worthiness and user inconvenience such as bad drivability during engine warm up phase. This paper presents fuel injector technologies capable of rapidly electrically heating the ethanol fuel for the Brazilian transportation market.

Heavy duty diesel engine development has always faced high customer durability requirements, short development timelines and increasingly stringent emissions legislations. However, more frequently heavy duty engines are being used in multiple vehicle platforms across the globe with increasingly stringent quality demands in emerging markets. In order to meet engine life requirements, Delphi Diesel Systems has adapted accepted validation procedures to evaluate their system performance for the global market. In addition to durability and structural testing Delphi Diesel Systems has introduced specialized tests to validate their product at extremes of environmental conditions and fuel properties and has increased OEM collaboration. This paper details some of the adjustments made to the validation test suite to meet the specific challenges of the Heavy Duty market.

To meet future particulate number regulations, one path being investigated is higher fuel pressures for direct injection systems. At operating pressures of 30 MPa to 40 MPa, the fuel system components must be designed to withstand these pressures and additional power is required by the pump to pressurize the fuel to higher pressures than the nominal 15MPa to 20MPa in use today. This additional power to the pump can affect vehicle fuel economy, but may be partially offset by increases in combustion efficiency due to improved spray mixture preparation. This paper examines the impact on fuel economy from increased system fuel pressures from a combination of test results and simulations. A GDi pump and valvetrain model has been developed and correlated to existing pump torque measurements and subsequently used to predict the increase in torque and associated impact on fuel economy due to higher GDi system pressures.