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Stress analyses of complex automotive components can be nearly impossible to achieve due to extreme difficulties in generating a realistic finite element model. A digital image based finite element approach was used to generate a 3-D finite element model from computed tomography (CT) scans of two automotive transmission cases. For the first case, original CT slices of 1024x1024x208 provided by ARACOR Inc. (Sunnyvale, CA) were used to generate a 3-D finite element model containing nearly 400,000 8-node brick elements. For the second case, 770x870x759 CT slices were used to generate a 3-D finite element model containing approximately 650,000 3-D elements. The mesh data generation from CT data for both cases took 6 minutes each on an engineering workstation. The resulting finite element meshes were analyzed using a specially designed finite element equation solver.

A high-speed/high-resolution imaging technique and analysis were applied to study fuel injector spray timed evolution in ambient air and in a motored single-cylinder engine. Alcohol fuel was injected from a mid-pressure injection system into the engine cylinder at shaft speed of 1,000 rpm. The fuel injection system with various nozzles was designed for use in the EPA/NVFEL program to develop clean and efficient engines that use alternative fuels. A 15W copper vapor laser with a fiber optic delivery system synchronized with a high-speed drum streak camera was utilized to expose films at 5,000 frames per second (fps). The spray characteristics were investigated at 15.0 MPa injection pressure and injection duration range of 3-5 ms. A sequence of successive frames was selected from the films to examine the influence of the injector parameters and the valve lift on the atomization process. The spray penetration was quantified by analyzing the high-speed films.

The unitized construction Aerostar compact van and wagon models have been engineered to meet a variety of consumer transportation needs. The broad range of functional and image objectives have been attained by traditional design and development programs augmented by new developmental methods and isolation components. State-of-the-art development methodologies applied early in the Aerostar program enabled prediction of the effects of design revisions intended to improve subsystem response characteristics and isolation. Developmental methods used included finite element analysis, modal analysis and synthesis, transmissibility measurements, torsional powertrain measurements, continuous wave laser holography, acoustical mode determination, acoustical intensity mapping and sensitivity studies used to project production ranges of quality.

The aerodynamic development and characteristics of a four-passenger advanced concept automobile are described. An overview of the areas of the vehicle design which were dealt with to obtain a drag coefficient value of 0.153 is provided. The interior packaging philosophy is outlined which led to the potential for packaging four to six passengers within an extremely low drag automobile. Parametric shape studies of the major surface design elements are documented from the contributing development testing. The particular design treatments adopted and the rationale behind the choice of design are examined for each of the aerodynamically-sensitive areas of the vehicle. Examinations of the unique solutions to vehicle cooling, ramp and curb clearance, front wheel skirting and vehicle attitude are presented. Full scale wind tunnel data is shown for the configurations examined and vehicle stability parameters compared with conventional vehicles.