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This report presents the results of a CFD study to develop a bodywork package to improve the aerodynamic performance of the Brigham Young University (BYU) Electric Streamliner. A comparison of the pressure distribution and the flow around the baseline and final ‘recommended’ configuration is also presented. The effect of the CFD developed body geometry to the vehicle has been to increase downforce by almost 300lbf when it is at 200mph, while reducing drag by 8.5lbf. The final lift to drag ratio is -1.56 as compared to the .67 baseline.

Modern multi-grade engine lubricants are formulated to “stay in grade” during field service. Viscosity loss during the early stages of lubricant life is commonly believed to be caused by mechanical degradation of the viscosity modifier in the engine [1]. The Kurt Orbahn shear stability bench test (ASTM D 6278, 30 cycles) has been the industry standard predictor of viscosity loss due to polymer shear in heavy duty diesel engine lubricants. However, the Engine Manufacturers' Association (EMA) has expressed some concern that it underestimates the degree of polymer shear found in certain engines in the field, such as the Navistar 6.0L HEUI (Hydraulic Electronic Unit Injector) Power Stroke engine; a more severe bench test would serve to improve correlation with this and other similar engine designs. This paper offers a new approach for critically examining the relationship between the bench test and field performance.

A new gas phase kinetic model using Westbrook's gas phase n-heptane model and Frenklach's soot model was constructed. This model was then used to predict the impact on PAH formation as an indices of soot formation on ethanol/diesel fuel blends. The results were then compared to soot levels measured by various researchers. The ignition delay characteristics of ethanol were validated against experimental results in the literature. In this paper the results of the model and the comparison with experimental results will be discussed along with implications on the method of incorporation of additives and alternative fuels.

In API engine oil licensing, a candidate oil must meet the performance requirements of category defined engine tests. The reason for the engine tests is to assess the capability of the candidate oil in field performance. Unfortunately, due to the time consuming and expensive nature of most engine tests, a candidate oil is typically run only once or twice in an attempt to meet the performance requirements. Given that the results from most engine tests have large amounts of variability, the assessment of the candidate oil in several tests, although adequate, is obviously not perfect or inexpensive. The Virtual Engine Test is a process in which the time and expense of category defined engine tests may be reduced while maintaining, or even improving, the assessment of the candidate oil capability.

The concept of a seat with an active adjustable seatback stiffness for enhanced safety during a rear impact was published previously. Static testing of a demonstrative prototype is supplemented with repeated dynamic tests at various velocity / acceleration levels. These tests were performed with a Hybrid III Anthropomorphic Test Device (ATD) and demonstrate that the occupant response can be modified by engagement of the device based on the severity of the crash pulse and other factors. A mathematical model for the dynamic response of the seat and the correlated occupant response is in development. Refinement of this technology is complemented by results of the dynamic testing.

We present a geometrically exact isogeometric blended shell formulation. In other words, all geometric quantities appearing in the blended theory are evaluated exactly and no approximations are employed. The blended approach allows higher-order shell theories, like Kirchhoff-Love, to be combined with Reissner-Mindlin shell formulations, which have rotational degrees of freedom. In this way, rotations can be employed only where needed to simplify shell modeling such as at kinks and intersections. Away from these regions shear locking free formulations can be employed to improve robustness, accuracy, and efficiency. We compare our approach to standard shell elements commonly used in industry on several benchmarks to explore the behavior of the element. We then model an inner car hood to demonstrate our ability to handle complex CAD geometry in a simple manner without geometry cleanup and mesh generation steps.