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Gasoline Direct Injection (GDi) system is a relatively new technology. In early implementations, its major components, i.e. high pressure fuel pump, injectors, and fuel rails, emit objectionable acoustic noise during normal operation. This paper will focus on making an objective comparison (assessment) of acoustic noise emitted by several cam-driven high pressure fuel pumps during their normal operation, especially at engine idle. Taguchi robust engineering methods will be used to conduct the robust assessment study of six GDi high-pressure pumps. A-weighted total sound pressure level (SPL), processed from two free-field microphones around each pump, will be used as the main function in the Taguchi design of experiments (DOE).

Gasoline Direct injection (GDi) systems offer performance and /or fuel consumption advantages compared to the traditional lower pressure port fuel injected technology. One disadvantage of GDi is the higher level of audible noise produced by the high pressure GDi system components. Powertrain noise is a known warranty complaint across the automotive industry. This paper presents an objective comparison of acoustic noise emitted by eight solenoid actuated fuel injector designs during their normal operation, including at engine idle, where powertrain noise is more noticeable to the customer. Taguchi Robust Engineering methods will be used to conduct an assessment of the noise generated by various GDi fuel injector designs. Injector fixturing, measurement procedures, and their impact on reducing test-to-test measurement variation are discussed.

Safety is a key element in new vehicle design and active safety, together with driver distraction prevention, has become one of the most talked about issues in the mobility industry. This book features 20 SAE technical papers, originally published in 2009 and 2010, which showcase how the mobility industry is considering all aspects of safety in designing and producing safer vehicles. These papers were selected by SAE International's 2010 President Dr. Andrew Brown Jr., Executive Director and Chief Technologist for Delphi Corporation. The contents of this book explore a variety of safety issues in the areas of market and consumer preferences; driver assistance and modeling; active safety system, crash sensing and sensor fusion; communications; and road safety. The publication also includes a number of articles authored by renowned experts in the field of active safety.

Unburned hydrocarbon (UBHC) emissions from gasoline engines remain a primary engineering research and development concern due to stricter emission regulations. Gasoline engines produce more UBHC emissions during cold start and warm-up than during any other stage of operation, because of insufficient fuel-air mixing, particularly in view of the additional fuel enrichment used for early starting. Impingement of fuel droplets on the cylinder wall is a major source of UBHC and a concern for oil dilution. This paper describes an experimental study that was carried out to investigate the distribution and “footprint” of fuel droplets impinging on the cylinder wall during the intake stroke under engine starting conditions. Injectors having different targeting and atomization characteristics were used in a 4-Valve engine with optical access to the intake port and combustion chamber.

Wall-wetting due to liquid fuel film motion and fuel droplet impingement on combustion chamber walls is a major source of unburned hydrocarbons (UBHC), and is a concern for oil dilution in PFI engines. An experimental study was carried out to investigate the effects of injection timing, a charge motion control device, and the matching of injector with port geometry, on the “footprints” of liquid fuel inside the combustion chamber during the PFI engine starting process. Using a gasoline-soluble dye and filter paper deployed on the cylinder liner and piston top land surfaces to capture the liquid fuel footprints, the effects of the mixture formation processes on the wetted footprints can be qualitatively and quantitatively examined by comparing the wetted footprint locations and their color intensities. Real-time filming of the development of wetted footprints using a high-speed camera can also show the time history of the fuel wetting process inside an optically accessible engine.

Low-pressure, Cooled Exhaust Gas Recirculation (LPC EGR) brings significant fuel economy, NOx reduction and knock suppression benefits to a modern, boosted, downsized Spark Ignition (SI) engine. As a prerequisite to design an engine control system for LPC EGR, this paper presents development of a set of estimation algorithms to accurately estimate the flow rate, pressure states and thermal states of the LPC EGR-related components.

Estimation of vehicle roll angle, lateral velocity and side slip angle for the purpose of crash sensing is considered. Only roll rate sensor and the sensors readily available in vehicles equipped with ESC (Electronic Stability Control) systems are used in the estimation process. The algorithms are based on kinematic relationships, thus avoiding dependence on vehicle and tire models, which minimizes tuning efforts and sensitivity to parameter variations. The estimate of roll angle is obtained by blending two preliminary estimates, each valid in different conditions, in such a manner that the final estimate continuously favors the more accurate one. The roll angle estimate is used to compensate the gravity component in measured lateral acceleration due to vehicle roll or road bank angle. This facilitates estimation of lateral velocity and side slip angle from fundamental kinematic relationships involving the gravity-compensated lateral acceleration, yaw rate and longitudinal velocity.

A gasoline compression-ignition combustion system is being developed for full-time operation over the speed-load map. Low-temperature combustion was achieved using multiple late injection (MLI), intake boost, and moderate EGR for high efficiency, low NOx, and low particulate emissions. The relatively long ignition delay and high volatility of RON 91 pump gasoline combined with an advanced injection system and variable valve actuation provided controlled mixture stratification for low combustion noise. Tests were conducted on a single-cylinder research engine. Design of Experiments and response surface models were used to evaluate injection strategies, injector designs, and various valve lift profiles across the speed-load operating range. At light loads, an exhaust rebreathing strategy was used to promote autoignition and maintain exhaust temperatures. At medium loads, a triple injection strategy produced the best results with high thermal efficiency.

This book features 20 SAE technical papers, originally published in 2009 and 2010, which showcase how the mobility industry is developing greener products and staying responsive - if not ahead of - new standards and legal requirements. These papers were selected by SAE International's 2010 President Dr. Andrew Brown Jr., Executive Director and Chief Technologist for Delphi Corporation. Authored by international experts from both industry and academia, they cover a wide range of cutting-edge subjects including powertrain electrification, alternative fuels, new emissions standards and remediation strategies, nanotechnology, sustainability, in-vehicle networking, and how various countries are also stepping up to the "green challenge".

A high-frequency electrical resonance-based ignition concept is in development to replace conventional spark ignition functionality for gasoline engines employing various types of fuel injection methods. The concept provides the benefit of a continuous discharge phase and the electrical power of the discharge can also be adjusted to the needs of the combustion conditions. This concept employs an alternative method of generating high voltages, using inductors and capacitors trimmed such that the supplied energy steadily increases the output voltage. This configuration is widely known as Tesla transformer and has been engineered to operate in a modern gasoline engine combustion environment. This development allows very high break down voltages to be generated and the power into the spark itself can be influenced.

This paper is an overview of the current state (calendar year 2010) of in-vehicle multiplexing and what pertinent technologies are emerging. Usage and trends of in-vehicle networking protocols will be presented and categorized. The past few years have seen a large growth in the number and type of communication buses used in automobiles, trucks, construction equipment, and military, among others. Development continues even into boating and recreation vehicles. Areas for discussion will include SAE Class A, B, C, Diagnostics, SafetyBus, Mobile Media, Wireless, and X-by-Wire. All existing mainstream vehicular multiplex protocols (approximately 40) are categorized using the SAE convention as well as categories previously proposed by this author. Top contenders will be pointed out along with a discussion of the protocol in the best position to become the industry standard in each category.

Modern automatic transmissions use various methods to estimate fluid line pressures in order to improve shift quality and reduce energy losses. These estimations lead to improvements in fuel economy, customer satisfaction and reduced exhaust emissions. The further addition of pressure feedback switches improves operational knowledge by verifying when clutches have received their commanded pressures. Product reliability above the industry standard for transmission pressure switches was developed through the use of multiple FEA platforms combined with advanced design optimization software, robust optimization and Shainin® tools. In this optimized design, ferromagnetic non-contact pressure switches operate by translating fluid pressure into piston motion, isolated by a sealed proprietary diaphragm.

During the past decade, there has been a steady increase in studies addressing rollover crashes and injuries. Though rollovers are not the most frequent crash type, they are significant with respect to serious injury and interest in rollovers has grown with the introduction of SUVs, vans, and light trucks. A review of Occupant and Vehicle Responses in Rollovers examines relevant conditions for field roll overs, vehicle responses, and occupant kinetics in the vehicle. This book edited by Dr. David C. Viano and Dr. Chantal S. Parenteau includes 62 technical documents covering 15 years of rollover crash safety, including field crash statistics, pre- and rollover dynamics, test procedures and dummy responses.

Brazilian ethanol vehicles are typically equipped with an auxiliary gasoline sub-tank fuel system which aids cold starting and drivability for low ambient temperatures. Port fuel injectors capable of rapidly heating ethanol have been developed to eliminate this auxiliary system. These injectors also enable reductions in emissions. Computational Fluid Dynamics (CFD) is used in conjunction with Taguchi Robust Engineering methods to optimize the heat exchanging geometry of these heated injectors. Simulation results are confirmed with experimental hardware and engine cold start testing. Modeling results, experimental hardware, and engine cold start performance is presented and discussed.