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A typical monolithic catalyst consists of long, narrow, square channels containing a washcoat of catalytic material. While this geometry is the most common, other shapes may be better suited for particular applications. Of interest are hexagonal, triangular, and circular channel geometries. This paper provides a succinct review of these channel shapes and their associated heat and mass transfer correlations when used in a one plus one-dimensional model including diffusion in the washcoat. In addition, a summary of the correlations for different mechanical and thermal stresses and strains are included based on channel geometry. By including the momentum equation in the model formulation with geometry specific friction factors, this work illustrates a unique optimization procedure for light off, pressure drop, and lifetime operation according to a desired set of catalyst specifications. This includes the recalculation of washcoat thickness and flow velocity through the channels when cell density changes.

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The original use of the vehicle dashboard was to provide enough sensory information to inform the driver of the current engine and vehicle status and performance. Over time, it has evolved into an entertainment system that includes person-to-person communication, global positioning information, and the Internet, just to name a few. Each of these new features adds to the amount of information that drivers must absorb, leading to potential distraction and possible increases in the number and types of accidents. In order to provide an overview of these issues, this paper summarizes previous work on driver distraction and workload, demonstrating the importance of addressing those issues that compete for driver attention and action. In addition, a test platform vehicle is introduced which has the capability of assessing modified dashboards and consoles, as well as the ability to acquire relevant driving performance data. Future efforts with this test platform will be directed toward helping to resolve the critical tug-of-war between providing more information and entertainment while keeping drivers and their passengers safe. The long-term goal of this research is to evaluate the various technological innovations available for inclusion in the driving environment and determining how to optimize driver information delivery without excessive distraction and workload. The information presented herein is the first step in that effort of developing an adaptive distraction/workload management system that monitors performance metrics and provides selected feedback to drivers. The test platform (1973 VW Beetle converted to a plug-in series hybrid) can provide speed, location (GPS), 3-D acceleration, and rear proximity detection. The test drive route was a 2 km × 3 km city street circuit which took approximately 25 minutes to complete. Data is provided herein to demonstrate these capabilities. In addition, the platform has driver selectable layouts for the instrument cluster and console (LCD screens). The test platform is planned for use to determine driver preferences (e.g., dashboard/console configurations) and attention performance in addition to identifying optimal real-time feedback for drivers with different demographics.

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