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The use of composite materials in the automotive industry has become increasingly widespread. With this increase in use, techniques for non-destructive testing (NDT) have become more and more important. Various optical NDT inspective methods such as holography, moiré techniques, and shearography have been used for material testing. Among these methods, shearography appears to be most practical. Shearography has a simple optical setup due to its “self-referencing” system, and it is relatively insensitive against rigid-body motions. Measurements of displacement derivatives, and thus strain directly, rather than the displacement itself is achieved through this method. Therefore shearography detects defects in objects by correlating anomalies of strain which are usually easier than correlating the anomalies of the displacement itself, as in holography. To date shearography has shown potential as a NDT tool for identifying defects in small structures.

In a campaign to quantify the aerodynamic drag changes associated with drag reduction technologies recently introduced for light-duty vehicles, a 3-year, 24-vehicle study was commissioned by Transport Canada. The intent was to evaluate the level of drag reduction associated with each technology as a function of vehicle size class. Drag reduction technologies were evaluated through direct measurements of their aerodynamic performance on full-scale vehicles in the National Research Council Canada (NRC) 9 m Wind Tunnel, which is equipped with a the Ground Effect Simulation System (GESS) composed of a moving belt, wheel rollers and a boundary layer suction system. A total of 24 vehicles equipped with drag reduction technologies were evaluated over three wind tunnel entries, beginning in early 2014 to summer 2015. Testing included 12 sedans, 8 sport utility vehicles, 2 minivans and 2 pick-up trucks.

A multi-year, multi-vehicle study was conducted to quantify the aerodynamic drag changes associated with drag reduction technologies for light-duty vehicles. Various technologies were evaluated through full-scale testing in a large low-blockage closed-circuit wind tunnel equipped with a rolling road, wheel rollers, boundary-layer suction and a system to generate road-representative turbulent winds. The technologies investigated include active grille shutters, production and custom underbody treatments, air dams, wheel curtains, ride height control, side mirror removal and combinations of these. This paper focuses on mean surface-, wake-, and underbody-pressure measurements and their relation to aerodynamic drag. Surface pressures were measured at strategic locations on four sedans and two crossover SUVs.

Terrestrial winds play an important role in affecting the aerodynamics of road vehicles. Of increasing importance is the effect of the unsteady turbulence structure of these winds and their influence on the process of optimizing aerodynamic performance to reduce fuel consumption. In an effort to predict better the aerodynamic performance of heavy-duty vehicles and various drag reduction technologies, a study was undertaken to measure the turbulent wind characteristics experienced by heavy-duty vehicles on the road. To measure the winds experienced on the road, a sport utility vehicle (SUV) was outfitted with an array of four fast-response pressure probes that could be arranged in vertical or horizontal rake configurations that provided measurements up to 4.0 m from the ground and spanning a width of 2.4 m. To characterize the influence of the proximity of the vehicle on the pressure signals of the probes, the SUV and its measurements system was calibrated in a large wind tunnel.

Internal combustion engines continue to grow more complex every day out of necessity. Legislation and increasing customer demand means that advanced technologies like variable valve actuation (VVA), multi-path exhaust gas recirculation (EGR), advanced boosting, and aftertreatment systems continue to drive ever-expanding requirements for engine control to improve performance, fuel economy, and reduce emissions. Therefore, controller development and implementation are becoming more costly, both in terms of time and the monetary investment in engine hardware. To help reduce these costs, a sophisticated tool chain has been created which allows a real-time, physical, crank-angle resolved one-dimensional (1D) engine model to be implemented on a rapid prototyping engine control unit (ECU) which is then used in the control strategy of a running engine. Model-based controllers have been developed and validated to perform as well as or better than controllers using traditional sensors.