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With increasingly stringent emissions regulations and concurrent requirements for enhanced engine thermal efficiency, a comprehensive characterization of the automotive gasoline fuel spray has become essential. The acquisition of accurate and repeatable spray data is even more critical when a combustion strategy such as gasoline direct injection is to be utilized. Without industry-wide standardization of testing procedures, large variablilities have been experienced in attempts to verify the claimed spray performance values for the Sauter mean diameter, Dv90, tip penetration and cone angle of many types of fuel sprays. A new SAE Recommended Practice document, J2715, has been developed by the SAE Gasoline Fuel Injection Standards Committee (GFISC) and is now available for the measurement and characterization of the fuel sprays from both gasoline direct injection and port fuel injection injectors.

A 2D model for vehicle-to-vehicle impact analysis that was presented in an earlier paper [1], has been used to study several two-vehicle frontal impacts with different incidence angles, frontal overlap offsets, and mass ratios. The impacts have been evaluated in terms of energy and momentum change in the bullet vehicle and the target vehicle. Based on comparisons between pre- and post-impact longitudinal, lateral, and angular components of kinetic energy, and linear and angular momenta, the impacts experienced by the target vehicle and the bullet vehicle have been classified as collinear or oblique. These results have been used to propose a definition of frontal impact based on vehicle kinematics during a crash.

A process for simultaneously optimizing the mechanical performance and minimizing the weight of an automotive body-in-white will be developed herein. The process begins with appropriate load path definition though calculation of an optimized topology. Load paths are then converted to sheet metal, and initial critical cross sections are sized and shaped based on packaging, engineering judgment, and stress and stiffness approximations. As a general direction of design, section requirements are based on an overall vehicle “design for stiffness first” philosophy. Design for impact and durability requirements, which generally call for strength rather than stiffness, are then addressed by judicious application of the most recently developed automotive grade advanced high strength steels. Sheet metal gages, including tailored blanks design, are selected via experience and topometry optimization studies.

This paper presents a Power-Based Noise Reduction (PBNR) concept and uses PBNR to set vehicle acoustic specifications for sound package design. This paper starts with the PBNR definition and describes the correct measurement techniques. This paper also derives the asymptotic relationships among PBNR, conventional noise reduction (NR), and sound transmission loss, for a simple case consisting of the source, path, and receiver subsystems. The advantages of using PBNR over conventional Noise Reduction (NR) are finally demonstrated in vehicle measurement examples.

Recently published SAE Recommended Practice J2562 - SAE Biaxial Wheel Test standardized the terminology, equipment, and test procedure for the biaxial wheel test. This test was originally presented by Fraunhofer Institut Betriebsfestigkeit - LBF (Fraunhofer Institute for Structural Durability) in SAE paper 830135 “Automotive Wheels, Method and Procedure for Optimal Design and Testing”. The first release of SAE J2562 included a generic, scalable load file applicable to wheels designed for five to eight passenger vehicles with capacity to carry a proportional amount of luggage or ballast. Future releases of SAE J2562 would include two additional load files; one applicable to light trucks that have substantial cargo capacity and one for sports cars typically limited to two passengers and marginal luggage. This report details the process used to develop the SAE Biaxial Wheel Test Load File for passenger vehicles.

Different countermeasure designs for reducing the HIC (d) and to comply with FMVSS201U have been evaluated in many component-level studies by suppliers and OEMs. This study presents guidelines to support future countermeasure and interior designs. FMVSS201U has changed the way OEMs design interiors of the vehicles today. Most recently, much more work is being done to find ways to design interiors of the vehicles that comply with FMVSS201U while keeping the interiors aesthetically pleasing, attaining driver comfort and meeting driver visibility requirements. Introduction of side-rail airbags has further affected countermeasure design and packaging. This study focuses on several countermeasure designs in the side-rail region as used in a mid-sized vehicle implemented to meet FMVSS201U requirements and their efficiency with respect to Head Injury Criterion (HIC) reduction given a fixed packaging space.

Vehicle requirements are measurable and define the performance of a system and its design constraints. Requirements are developed and translated from the voice of the buying customer, the voice of the government, and the voice of General Motors. Duramax powertrain subsystem requirements are developed from the vehicle requirements. This “flow down” approach optimizes the vehicle as a system. The packaging envelope, common interfaces, and manufacturing impacts were the outcome of the Vehicle Portfolio Development Process. Project execution was a global development process executed by Isuzu Engineers in Japan, Allison Automatic Transmission Engineers in Indianapolis, ZF Manual Transmission Engineers in Detroit, and General Motors Engineers in Detroit.

Vehicle evaluations and model calculations were conducted on a vacuum-insulated catalytic converter (VICC). This converter uses vacuum and a eutectic PCM (phase-change material) to prolong the temperature cool-down time and hence, may keep the converter above catalyst light-off between starts. Tailpipe emissions from a 1992 Tier 0 5.2L van were evaluated after 3hr, 12hr, and 24hr soak periods. After a 12hr soak the HC emissions were reduced by about 55% over the baseline HC emissions; after a 24hr soak the device did not exhibit any benefit in light-off compared to a conventional converter. Cool-down characteristics of this VICC indicated that the catalyst mid-bed temperature was about 180°C after 24hrs. Model calculations of the temperature warm-up were conducted on a VICC converter. Different warm-up profiles within the converter were predicted depending on the initial temperature of the device.

General Motors Powertrain Group (GMPTG) has developed an all new small block V8 engine, designated LS1, for introduction into the 1997 Corvette. This engine was designed to meet both customer requirements and competitive challenges while also meeting the ever increasing legislated requirements of emissions and fuel economy. This 5.7L V8 provides increased power and torque while delivering higher fuel economy. In addition, improvements in both QRD and NVH characteristics were made while meeting packaging constraints and achieving significant mass reductions.

General Motors Powertrain Division has developed the next generation big block V8 engine for introduction in the 1996 model year. In addition to meeting tighter emission and on-board diagnostic legislation, this engine evolved to meet both customer requirements and competitive challenges. Starting with the proven dependability of the time tested big block V8, goals were set to substantially increase the power, torque, fuel economy and overall pleaseability of GM's large load capacity gasoline engine. The need for this new engine to meet packaging requirements in many vehicle platforms, both truck and OEM, as well as a requirement for minimal additional heat rejection over the engine being replaced, placed additional constraints on the design.