Performance appraisal of a four-stroke hydrogen internal combustion engine

Fossil fuel depletion and environmental factors had lead the search for alternative transportation fuels. One such alternative is hydrogen. Of the potential transportation fuels of the future hydrogen is the only one which is both sustainable and environmentally friendly. A good understanding of the quantitative and qualitative trends are available in the literature, for petrol driven vehicles, as established knowledge. However, understanding of the near zero emissions and associated conversion technology, using hydrogen as fuel, has been in the domain of few automotive applications around the world. This work is aimed at converting a commercially available vehicle to operate on hydrogen as a design and manufacturing exercise to showcase the use of alternative fuel. The chosen vehicle is the Honda CT110 motor bike or better known as the Australia Post `postie bike'. In this thesis, a rigorous design process for conversion to hydrogen is proposed and implemented from first principles. The test rig development associated with the calculations for fuel flow rates and associated engine management systems are an integral part of this overall systematic design. As part of the investigation an innovative fuel injection system together with fuel-air-intake system is designed and incorporated. Traditional problems with pre-ignition in hydrogen engines are found to be minimized by developed systematic design techniques. As part of this investigation a comprehensive range of engine operating conditions are investigated using both petrol and hydrogen as fuel. The comparisons have shown that for the same operating conditions, hydrogen powered vehicles suffer losses in power and thermal efficiency. With the performance requirements of the vehicle in mind the reductions in performance are not seen as a major compromise. Exhaust emission performance showed significant reduction in oxides of nitrogen and no significant emissions of hydrocarbons, carbon dioxide and carbon monoxide. Future potential developments suggested by this work is expected to improve performance outputs further.