Battery electrified power is predicted to become the dominant mode of propulsion in future passenger cars. For long haul heavy duty transport challenges remain around practical range, payload and total cost. Currently there is no single economically viable decarbonised solution for heavy duty ground vehicles. Ammonia could form part of the ideal future mix, as a hydrogen energy vector or potentially through direct end use. The proposed work seeks to determine the energy and air quality impacts and potential future applications of a novel ammonia-fuelled heavy duty IC engine operating with high efficiency (c.50% brake) and zero emissions through a new fast burning combustion system. The project will evaluate potential reductions in energy demand in the 'green' ammonia production process, making use of the new green ammonia pilot plant at the Rutherford Appleton Laboratories. In order to assess relative advantages and challenges, the project will undertake evidence based life cycle analysis across a spectrum of competing decarbonised powertrain technologies for long range heavy duty transport (ground, freight rail and marine).

Ammonia, a highly hydrogenated molecule, has been identified as an important means to support a transition to hydrogen economy, as it can be used to store and distribute hydrogen easily because of the already existing infrastructure for transport and storage of ammonia. If hydrogen is to be extracted from ammonia at the point of use, the thermo-catalysis of ammonia back to hydrogen requires a high amount of energy. Preferably ammonia is used directly as a carbon-free liquid fuel for combustion engines in power generation, marine vessels and long-haul vehicles where batteries cannot be used due to their low energy density (hence large volume and weight), high cost and long charging times. However, the significantly lower energy density (as measured by calorific value) of ammonia requires much larger fuel storage space and weight to be used. More importantly, the direct application of ammonia in combustion engines suffers from incomplete combustion and poor engine performance due to ammonia's higher ignition energy, higher auto-ignition temperature as well as significantly lower flame speed. In order to address the aforementioned challenges of ammonia and hydrogen for their applications in transport, a new type of liquid ammonia blended with hydrogen will be researched and demonstrated in this project with advanced modelling and experimental techniques. The proposed novel fuel has both ammonia and hydrogen molecules, and will enable (1) immediate and wider use of carbon free ammonia and hydrogen in existing engines, particularly for long haul vehicles, marine vessels and power generators, (2) significantly improved engine performance and lower emissions through increased energy density, faster and complete combustion. Therefore, the developed liquid ammonia blended with hydrogen would enable an immediate, cost-effective and 100% reduction in CO2 emissions to achieve net zero target in long haul transport, shipping, and power generation sectors by and beyond 2050 that will be difficult to achieve with existing technologies in use or in development.

More than 80% of world energy today is provided by thermal power systems through combustion of fossil fuels. Because of their higher energy density and the extensive infrastructure for their supply, liquid fuels will remain the dominant energy source for transport for at least next few decades according to 2019 BP Energy Outlook report. In order to decarbonise the transport sector, the Intergovernmental Panel on Climate Change highlights the important role that biofuels and other alternative fuels such as hydrogen and e-fuels could, in some scenarios provide over 50% of transport energy by 2050. The importance of the renewable transport fuel is also recognized by the UK Government's revised Renewable Transport Fuel Obligation published in April 2018 which sets out the targeted amount of biofuels to 12.4% to be added to regular pump fuel by 2032. In practice, there are several obstacles which hinder the application of low-carbon and zero-carbon fuels. As a zero-carbon fuel, hydrogen can be produced and used as an effective energy storage and energy carrier at solar and wind farms. But its storage and transport remain a significant challenge for its wider usage in engines due to the complexity and substantial cost of setting up multiple fuel supply infrastructure and on-board fuelling systems. Although the low-carbon renewable liquid fuels, such as ethanol and methanol produced from hydrogen and CO2, can be used with the existing fuel supply systems, the significantly lower energy density, which is about half of that of gasoline/diesel, makes them unfavourable to be directly applied in the existing engines for various applications (e.g. automotive, flying cars, light aircraft, heavy duty vehicles, etc.) with high requirements on power density. Whilst there is a drive to move towards electrification to meet the reduction of the carbon emissions, it is vital to innovate developments in advanced hybrid electrical and engine powertrain to provide additional options for future low-carbon transport. This research aims to carry out ground-breaking research on three innovative technologies covering both fuels and propulsion systems: nanobubble fuels and Nano-FUGEN system, fuel-flexible BUSDICE and DeFFEG system. The technologies either in isolation or as a hybrid have the potential to make a major contribution in addressing the challenge of decarbonising the transport sector. At first, I will explore how the nanobubble fuel (nano-fuel) concept can be used as a carrier for renewable gas fuels in liquid fuels in the form of nanobubbles. The technology can be implemented with minimal new development to the combustions engines and hence has the potential to make immediate impact on reducing CO2 emissions through better engine efficiency and increased usage of renewable energy. Secondly, a novel 2-stroke fuel-flexible BUSDICE (Boosted Uniflow Scavenged Direct Injection Combustion Engine) concept will be systematically researched and will involve development work for adapting to be used with both conventional fossil fuels and low-carbon renewable fuels (e.g. ethanol and methanol) and simultaneously achieve superior power performance and ultra-low emissions. At last, based on the developed BUSDICE concept, a Dedicated Fuel-Flexible Engine Generator (DeFFEG) will be further developed by integrating a linear generator and a gas spring chamber, therefore enabling advanced electrification and hybridisation for a range of applications, including automotive, aviation and marine industries. Overall, the proposed project is an ambitious and innovative study on the fundamentals and applications of the proposed fuel and propulsion technologies. The research not only has great potential to bring about new and fruitful academic research areas, but also will help to develop next-generation fuel and propulsion technologies towards meeting Government ambitions targets for the future low-carbon and zero-carbon transport.

The use of scale resolving simulations (SRS) for single phase flow applications has already shown dramatic accuracy benefits. The term SRS encompasses methods resolving a greater spectrum of turbulence e.g. large eddy simulation (LES), quasi-direct numerical simulation and hybrid methods e.g. detached eddy simulation (DES). The purpose of this work is to extend these methods for multi-phase applications. The use of SRS for single-phase turbulent flows is an area of fluids mechanics that has been widely studied for the past twenty years but SRS of multi-phase flows remains a very understudied area. The project will develop a massively parallel, high-order, fully implicit (temporal and spatial), multi-phase scale resolving methodology and perform simulations of (1) a representative aero-engine bearing chamber, (2) a representative transmission system gear and (3) a continuous chemical reactor. It will demonstrate the next generation of multi-phase high-fidelity flow simulations. We will exploit novel computing hardware through the extension and use of a state of the art fully implicit parallel library developed at the University of Oxford. The library, which enables 'future proofing' of CFD codes for modern hardware architectures, has been shown to give a 27x speedup on a GPU compared with the Intel Math Kernel Library tri-diagonal solver on a CPU. The research will be led by Dr. Richard Jefferson-Loveday, Assistant Professor in the department of Engineering at Nottingham University. It will be undertaken in collaboration with industrial partners MAHLE Powertrain, Rolls-Royce, ROMAX and GSK.

Battery electrified power is predicted to become the dominant mode of propulsion in future light duty transport. For sustainable heavy duty applications challenges remain around practical range, payload and total cost. Currently there is no economically viable single solution. For commercial marine vessels the problem is compounded by long service lives, with bulk carriers, tankers and container ships the main contributors to greenhouse gases. Ammonia (NH3) has excellent potential to play a significant role as a sustainable future fuel in both retrofitted and advanced engines. However, significant uncertainties remain around safe and effective end use, with these unknowns spanning across fundamental understanding, effective application and acceptance. This multi-disciplinary programme seeks to overcome the key related technical, economic and social unknowns through flexible, multidisciplinary research set around disruptive NH3 engine concepts capable of high thermal efficiency and ultra low NOx. The goal is to accelerate understanding, technologies and ultimately policies which are appropriately scaled and "right first time".