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The emergence of fuel cell powertrains has opened up new pathways to net-zero greenhouse gas emissions across a number of sectors, including public transport. However, while these technologies are gaining momentum, they are mostly still in their infancy with a range of fundamental challenges which still need to be addressed. The typical configuration deployed in bus applications requires integration with other fast-response power sources, e.g., battery and/or ultra-capacitor, to effectively manage power delivery. However, implementation of such hybrid energy storage systems (ESSs) complicates the design and control of the vehicle powertrains. In this work, a concept fuel cell bus vehicle powertrain configuration has been constructed first using Matlab/Simulink which can be used to explore the impact of various ESS hybridization strategies, and their effectiveness in power management.

The need to decrease greenhouse gases emissions in the transport sector has resulted in the requirement for zero emission technologies in city centre bus fleets. Currently, battery electric buses are the most common choice, with both single deck and double deck vehicles in regular use. However, long-term operational capabilities are still largely unknown and unreported. Hydrogen fuel cell electric buses are an emerging zero emission technology that have the potential to complement a battery electric bus fleet where the duty cycle is challenging for current battery electric configurations. This paper compares the difference in energy consumption, for a given chassis configuration, passenger load, and heating requirement, of generic battery electric and hydrogen fuel cell electric buses operating in a typical UK city environment.

Electric and Hybrid-Electric buses have become a major vehicle platform for demonstrating the advantages and capabilities of electrification in heavy duty vehicles. This type of vehicle can be powered from several different sources that each have several unique operating characteristics and performance requirements that necessitate novel solutions. In this paper, a novel optimal control strategy based on the next generation range-extended electric bus (REEB) has been developed. Control strategies play an essential role in realizing the full potential of electric buses and through careful implementation can increase their effectiveness at displacing conventional internal-combustion powered buses and thus, reducing global fuel consumption and emissions. Initially, a control-oriented powertrain model was developed in Matlab/Simulink.

The Formula SAE competition challenges engineering students to design, build and compete in a single-seat race car. The rules limit the swept volume of the engine to 610cc and so most teams elect to use a motorcycle engine which inherently offers the desirable attributes of high power density and low mass. Engines from 600 cc motorcycles designed primarily for road use are particularly common in this competition. When used in the motorcycle these engines rarely suffer from oil starvation induced by lateral acceleration as the engine tilts with the motorcycle during cornering thereby keeping the oil pickup submerged in the oil. However, when installed in the race car, the engine is constrained in the horizontal plane and is also subjected to higher lateral accelerations. This causes oil surge during cornering and results in almost instant and catastrophic engine failure. The Queens Formula Racing (QFR) team uses an 03-04 model, 600 cc Yamaha YZF R6 engine for their Formula SAE car.

Restricting the flow rate of air to the intake manifold is a convenient and popular method used by several motor sport disciplines to regulate engine performance. This principle is applied in the Formula SAE and Formula Student competitions, the rules of which stipulate that all the air entering the engine must pass though a 20mm diameter orifice. The restriction acts as a partially closed throttle which generates a vacuum in the inlet plenum. During the valve overlap period of the cycle, which may be as much as 100 degrees crank angle in the motorcycle engines used by most FSAE competitors, this vacuum causes reverse flow of exhaust gas into the intake runners. This, in turn, reduces the amount of fresh air entering the cylinder during the subsequent intake stroke and therefore reduces the torque produced. This effect is particularly noticeable at medium engine speeds when the time available for reverse flow is greater than at the peak torque speed.

The objective of the study outlined in this paper was to optimize the performance of a 600cc four-cylinder FSAE engine through the use of one-dimensional simulation. The first step in this process was to validate a baseline model of the engine in its stock, unrestricted format. This was achieved through the use of crank-angle-resolved and cycle-averaged test data. The in-cylinder pressure history was also analyzed to provide combustion and friction data specific to this engine. This process significantly improved the correlation of the model with the test data and it was subsequently used to simulate and optimize the configuration of the engine planned for use in the 2008 FSAE competition. The process of validating the model, together with the specification of the subsequent optimized engine, are presented.