Background
High pressure common rail diesel fuel injection equipment (FIE) for passenger cars and trucks are operating at ever-increasing pressures. A significant fraction of the diesel fuel supplied to the pump and injectors is returned to the tank after passing through fuel return valves. The diesel fuel flow through the return valves is believed to develop into a multi-phase cavitating flow, which may cause some fuel pyrolysis.
The overall aims of the project are: (1) to establish experimentally the effect of hydrodynamic cavitation on various diesel fuel samples, and (2) to identify the likely fuel pyrolysis reaction paths and rates leading to soot-like particle formation in the context of cavitation bubble collapse.
The aims of the project are to be achieved by: (1) subjecting the diesel fuel samples to continuous high pressure hydrodynamic cavitation in a purpose-built cavitation flow rig, (2) heating the fuel samples in a high temperature water/oil bath, (3) continuous measurement of the spectral extinction coefficient of the cavitated diesel, (4) gravimetric analysis, uv-visible absorption spectrometry and laser particle sizing in cavitated diesel samples, (5) off-site GCxGC testing of cavitated diesel samples, and (6) chemical kinetic modelling of diesel fuel pyrolysis in the context of cavitation bubble collapse.
The experiments will be conducted in the Applied Thermodynamics Laboratory (incorporated into the Research Centre for Energy & Transport) at City University London, under the supervision of Dr Russel Lockett and Professor Jamshid Nouri. The Applied Thermodynamics Laboratory incorporates the work of twelve investigators conducting experimental and modelling research in screw machinery, high speed turbo-machinery, engines, fuel injection systems, fuels, combustion, and applied optical diagnostics, employing five technicians, and including approximately thirty PhD students.
The studentship is available immediately for a period of three years, covers full UK/EU PhD tuition fees, and provides a tax-free stipend at the rate of £15,000 per annum for the duration of the project.
Responsibilities
The PhD candidate will be responsible for designing and developing a set of hardened nozzles, and undertaking a range of cavitation flow experiments and spectroscopy measurements on a set of commercial and secret diesel fuels, and model fuel blends of paraffins and aromatics. The candidate will also undertake chemical kinetic modelling of diesel fuel pyrolysis in the context of cavitation flow and cavitation bubble collapse. The candidate will be responsible for reporting his/her results in agreement with the standards set by the University and submit papers for peer review journals or relevant international conferences.
Person Specification
A good MEng/MSc degree (1st Class or 2/1 equivalent) in Mechanical Engineering or Chemical Engineering, or an equivalent MSc in Physics or Chemistry, is required. Applicants with a 1st Class BSc (Hons) degree in Physics and/or Chemistry will also be considered. Some experience in experimental fluid mechanics, chemical kinetic modelling and/or laser spectroscopy is desirable.
Additional Information
If you require further information please contact Dr Russel Lockett, Department of Mechanical Engineering & Aeronautics, School of Engineering and Mathematical Sciences, City University London, London, EC1V 0HB, or via email: r.d.lockett@city.ac.uk. Applicants should send a letter of application and their CV to Dr Lockett by email.
Closing date: 13 December 2013