Conventional energy carriers such as diesel and natural gas have been extensively studied in the literature and various models have been developed and tailored to the physical and thermochemical properties of these fuels. On the other hand, very little is still known about the thermochemical behaviour of alternative fuels under realistic operation conditions. Performing lab experiments with all the possible combinations of fuels and conditions to determine the optimum operability manifold is expensive and not always accurate, mainly because of the optical limitations of experimental techniques at the hostile high pressure and temperature combustor environment. This lack of knowledge raises considerable safety issues and design limitations obliging the manufacturers to restrict the use of alternative energy carriers to low percentage blends. For example, in IC engines bio-diesel is used at up to 5% while syngas is used up to 15% in gas turbines.
This affects both the emission characteristics of modern energy systems as well as their capacity to deal with energy storage from renewable sources. Synthetic fuels, apart from low carbon fuels, can also be used as an excellent way of storing thermal energy coming from the sun in large power plants through the reforming process of methane. Tools that can help diversify the energy mixture with alternative energy carriers and contribute to the design of less polluting thermal-propulsion systems are a key industrial priority.
The suggested project aligns with this priority and aims to bring our understanding and design capabilities of power and transportation systems operating with alternative energy carriers to a qualitatively new level with the development of a novel sophisticated Computational Fluid Dynamic (CFD) tool. The tool will be able to accurately simulate flow dynamics under extreme thermodynamic conditions of real-life applications when a diverse energy carrier input is used. The novelty of the project lies in the derivation of hybrid equations of state that can be dynamically activated depending on the local thermodynamic properties as well as chemical characteristics of the fuel input.
This is particularly important since the tool is aimed at allowing, for the first time, the unified modelling of all the phases of energy production in a combustion device from fuel injection to emissions. Thus, modelling of both very low pressure (injection nozzle) and high pressure (combustion) conditions must be accounted for and a single equation of state is not sufficient.
The project objectives are:
- develop a novel hybrid scheme to calculate thermodynamic properties of synthetic and bio-derived fuels under extreme thermodynamic conditions
- integrate the scheme to the CFD tool currently under development at the AEC through complementary EPSRC funding (EP/P012744/1 (Dr Vogiatzaki is PI), EP/M009424/1 (Dr Morgan is PI and Dr Vogiatzaki Co-I)) that model fuel injection ignition and combustion in a unified manner
- validate the tool against data provided by the project partners (Ricardo, MIT) for conditions relevant to both IC engines and gas turbines
- use the developed framework as a virtual testing tool to explore the effect of various fuels on GHG emissions under different conditions.
The successful candidate will be based within the University of Brighton's Advanced Engineering Centre and will undertake leading-edge modelling research in using state-of-the-art facilities. The PhD student will present findings at project review meetings with the partner industry (Ricardo), as well as at national and international conferences and will produce high impact journal publications.