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This paper describes the equipment, analysis methods and results obtained for particle size measurements based on a particle imaging velocimetry (PIV) system in which a short duration laser pulse is used to backlight airborne particles. This produces high quality and high resolution images of fast moving airborne particles in a non-intrusive manner. This imaging technique is also used to examine particle morphology and 2D particle trajectory and velocity. The image analysis methods are outlined and validation test results discussed which show the measurement of reference glass beads between 20 and 400 microns were generally to within their stated size. As well, validation testing using known icing wind tunnel droplet distributions were compared with Spraytek 2000 Malvern droplet size measurements and showed agreement of the MVD's to be within ±5% for distributions having nominally 20, 40 and 80 micron MVD's.

This paper describes the performance attributes of the all-new front and rear SLA (short-long arm) suspensions, steering system, and tires of the 1997 Corvette. The process by which these subsystem attributes flowed down from vehicle-level requirements for ride and handling performance is briefly described. Additionally, where applicable, specific subsystem attributes are rationalized back to a corresponding vehicle-level performance requirement. Suspension kinematic and compliance characteristics are described and contrasted to those of the previous generation (1984 to 1996 Model Year) Corvette. Both synthesis/analysis activities as well as mule-level vehicle development work are cited for their roles in mapping out specific subsystem attributes and related vehicle performance.

The complexity of designing and implementing a vehicle electrical control system for ultra fuel-efficient hybrid vehicles is significantly greater than that of a conventional vehicle. To quickly demonstrate and iterate capabilities of these vehicles, an efficient and rapid means for developing requirements, mapping these into an electrical control and communications architecture, and developing prototype systems is needed. The General Motors Precept concept vehicle is an example of an energy- efficient vehicular control system developed using a "requirements to software'' development process and electronic controller infrastructure that demonstrates these attributes. The Precept is General Motors Corporation's technology demonstration concept vehicle developed to address General Motors Corporation's commitment to the Partnership for a New Generation (PNGV) program.

Autonomous vehicles are currently a subject of great interest and there is heavy research on creating and improving algorithms for detecting objects in their vicinity. A ROS-based deep learning approach has been developed to detect objects using point cloud data. With encoded raw light detection and ranging (LiDAR) and camera data, several basic statistics such as elevation and density are generated. The system leverages a simple and fast convolutional neural network (CNN) solution for object identification and localization classification and generation of a bounding box to detect vehicles, pedestrians and cyclists was developed. The system is implemented on an Nvidia Jetson TX2 embedded computing platform, the classification and location of the objects are determined by the neural network. Coordinates and other properties of the object are published on to various ROS topics which are then serviced by visualization and data handling routines.

The aerodynamic forces experienced by vehicles depend on a variety of factors including wind direction, traffic, and roadside vegetation. Such complex boundary conditions often result in unsteady flow separation and the formation of large-scale coherent structures, which, in turn, significantly influence the aerodynamics of following vehicles. To gain a deeper understanding of the unsteady behaviour of such vehicle wakes under large-scale conditions, a time-resolved field measurement technique is required. Existing methods, such as tomographic particle image velocimetry and three-dimensional particle tracking velocimetry are unfortunately quite limited at these scales. Furthermore, such techniques require complex multi-camera calibrations, hazardous lasers, and optical access from many vantage points.

Intermittent and highly transient dense diesel sprays were investigated using laser diffraction and laser sheet illumination techniques to decipher the internal spray structure. Through careful experimental design, the unperturbed structure of the dense core region of a transient full cone diesel spray was observed for the first time. Diffraction measurements showed that larger droplets exist at the spray periphery and the Sauter mean diameter decreases from the periphery to the spray centerline. The results from both laser diffraction and 2-D imaging are inconsistent with the existence of an intact liquid core extending to a few hundred nozzle diameters. The intermittent and highly transient nature of diesel sprays ensures rapid and complete atomization within no more than twenty nozzle diameters.

Under contract to Transport Canada (TC) and with joint funding support from the Federal Aviation Administration (FAA), a vertical stabilizer common research model (VS-CRM) has been designed and built by the National Research Council of Canada (NRC). This model is a realistic, scaled representation of modern vertical stabilizer designs without being specific to a particular aircraft. The model was installed and tested in the NRC 3 m × 6 m Icing Wind Tunnel in late 2021/early 2022. Testing was led by APS Aviation Inc., with support from NRC and NASA, in order to observe the anti-icing fluids flow-off behavior with and without freezing or frozen precipitation during simulated take-off velocity profiles. The model dry-air aerodynamic properties were characterized using flow visualization tufts and boundary layer rakes. Using this data, a target baseline configuration was selected with a yaw angle equal to 0° and rudder deflection angle equal to -10°.

The use of carbon fiber reinforced thermoset composites has doubled in the last decade raising questions about the waste generated from manufacturing and at end-of-life, especially in the aircraft industry. In this study, 2.5 cm long carbon fibers were recovered from thermoset composite waste using a commercial scale pyrolysis process. Scanning electron microscopy, density measurements, single filament tensile testing as well as micro-droplet testing were performed to characterize the morphology, mechanical properties, and surface adhesion of the fibers. The recycled fibers appeared to be mostly undamaged and clean, exhibiting comparable mechanical properties to virgin carbon fibers. A carding process followed by an ultrasound treatment produced randomly aligned recycled fiber mats. These mats were used to fabricate composite plates, with fiber volume fractions up to 40 %, by infusion / compression molding.

The purpose of the Cadillac DeVille Night Vision System is to provide drivers with visual information beyond with the range of their headlamps. It can also help drivers see beyond the glare of oncoming vehicle’s headlamps. With increased visual range the driver may have more time to react to potentially dangerous situations. The system consists of a thermal imaging camera, a head-up display, and image controls. The camera senses temperature differences of objects in the road scene ahead and creates a thermal image of the scene. The head-up display projects this image onto the windshield creating a virtual image that appears at the front edge of the vehicle’s hood just below the driver’s line of sight. This paper will describe the system requirements and parameters of the 2000 Cadillac DeVille Night Vision system.

Continuous efforts to develop a lightweight alloy suitable for the most demanding applications in automotive industry resulted in a number of advanced aluminum (Al) and magnesium alloys and manufacturing routes. One example of this is the application of 319 Al alloy for production of 3.6L V6 gasoline engine blocks. Aluminum is sand cast around Fe-liner cylinder inserts, prior to undergoing the T7 heat treatment process. One of the critical factors determining the quality of the final product is the type, level, and profile of residual stresses along the Fe liners (or extent of liner distortion) that are always present in a cast component. In this study, neutron diffraction was used to characterize residual stresses along the Al and the Fe liners in the web region of the cast engine block. The strains were measured both in Al and Fe in hoop, radial, and axial orientations. The stresses were subsequently determined using generalized Hooke's law.