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The Nexus vehicle was designed and built for Transport Canada at the University of Saskatchewan to demonstrate that a safety compliant single passenger commuter vehicle could attain extremely low fuel consumption rates at modest highway speeds. Experimentally determined steady state fuel consumption rates of the Nexus prototype ranged from 1.6 L/100 km at 61 km/hr up to 2.8 L/100 km at 121 km/hr. Fuel consumption rates for the Society of Automotive Engineers (SAE) driving cycle tests were 4.5 L/100 km for the SAE Urban cycle and 2.0 L/100 km for the SAE Interstate 55 cycle. The efficiency of the power train was determined using a laboratory dynamometer, enabling the road test results to be compared to the results from an energy and performance simulation program. Predicted fuel economy was in good agreement with that determined experimentally. Widespread use of single passenger commuter vehicles would substantially reduce current transportation energy consumption.

In the presence of ambient winds, almost all present vehicles experience an increase in aerodynamic drag, which in turn causes an increase in energy consumption. However, it is possible to design a vehicle body shape that passively uses the wind to decrease aerodynamic drag and hence lower fuel consumption. This paper describes a scale-model wind tunnel investigation that studied vehicle-like shapes which exhibit a drag reduction, rather than a drag penalty, in crosswinds. The aerodynamic behavior of very-low-aspect-ratio, truncated, vertical airfoil sections close to the ground was studied to obtain a general idea of the behavior of these vehicle-like shapes. Force and surface pressure studies established that a significant drag reduction at low yaw angles could be achieved by attached flow over the leeward airfoil nose.

A testing and analysis method has been developed for the evaluation of the aerodynamic and rolling resistance coefficients of a vehicle, under windy weather conditions and on a road with some variation in grade. Over 100 coastdown runs have been collected and analyzed for the Transport Canada Nexus research prototype. Aerodynamic and rolling resistance functions have been found for the test vehicle for conditions from zero to over 30 degrees yaw, noting a characteristic in which aerodynamic drag decreases with yaw angle for Nexus. In addition, the effects of vehicle centripetal force due to road curvature in the vertical plane, lift force, velocity dependencies of rolling circumference and rolling resistance are discussed, and all are found to be negligible. The data analysis method developed, uses a computer-based simulation/optimization technique, which is described.

In this paper the authors compare the experimental load response of several welded aluminum structures with the response of equivalent finite element models. The samples tested represent frame components of NEXUS, a light weight research vehicle. The initial elastic response of thin walled specimens was accurately predicted using quadrilateral shell finite element models. Beam or shell element models were used to predict the elastic response of thick walled tubular samples. The material used to construct all of the samples was 0061-T6 aluminum. Tungsten inert gas welding was used to join the aluminum components. The heat of welding produced a heat affected zone with a large material property variation. The resultant difficulties with the accurate modelling of yield and post yield behaviour are discussed.