Building on the support provided by MariNH3 and other ongoing EPSRC research programmes in ammonia and hydrogen combustion for marine applications, the University of Brighton has secured two further projects funded by the Royal Academy of Engineering (RAEng) via the Transforming Systems through Partnership (TSP) scheme.

  • Phase I (TSP-2325-5-IN\145): November 2023-January 2025
  • Phase II (TSP-2526-7110): October 2025-January 2026

These projects focus on developing and applying direct injection liquid ammonia spray strategies to achieve zero-carbon emissions in marine and broader combustion applications.

In Phase I, an integrated experimental and simulation methodology was developed to investigate various ammonia delivery methods into engines, either indirectly via the intake port or by direct injection into the combustion chamber. In Phase II, the research emphasises experimental characterisation of liquid ammonia spray injection at engine-relevant conditions using a Rapid Compression Machine (RCM). This work explores how air entrainment and phase-change properties of liquid ammonia influence spray dynamics, air-fuel mixing and vaporisation, aiming to enhance overall combustion efficiency.

Key outputs

  • Optimised combustion strategies: development and evaluation of advanced ammonia/hydrogen fuel blends for marine applications – such as Reactivity-Controlled Compression Ignition (RCCI) engines – culminating in a roadmap for the sector to improve efficiency and reduce emissions.
  • Life Cycle Assessment (LCA): comprehensive environmental and economic analysis of the ammonia/hydrogen life cycle – from production to end-use, providing evidence-based guidance for sustainable energy policy.
  • Training and knowledge transfer: capacity building through training early career researchers and students in clean energy technologies, alongside knowledge exchange and dissemination with industry stakeholders and policymakers via workshops and publications.
Pictures of the first international workshop on Ammonia Combustion in India

The first international workshop on Ammonia Combustion (22 Nov. 2024) in India. Over 150 attendees; three presentations from University of Brighton by Dr A Panesar & Dr S Begg who also chaired sessions.

Challenges and solutions

During the project, several technical and operational challenges have been identified and addressed:

  • Combustion: a detailed combustion reaction mechanism for a liquid ammonia/gasoline fuel blend has been developed and validated using experimental data characterising laminar burning velocity. However, ignition delay and combustion characteristics have proven to be challenging with conventional test rigs. Consequently, the team proposes a more detailed investigation using the RCM to achieve deeper insights into the ignition delay of ammonia/hydrogen. This work will generate critical experimental data, invaluable to engine designers and fuel injection system manufacturers.
  • Engine modifications: successful implementation to accommodate dual-fuel ammonia/hydrogen combustion experimental activities using liquid ammonia in a dual-fuel mode were conducted to support ongoing computational fluid (CFD) modelling. These modifications represent a key milestone in demonstrating the technical feasibility of ammonia-based RCCI combustion.
  • Engine application: adapting ammonia/hydrogen combustion technology to practical marine engines introduces additional complexities for these fuels due to factors such as larger bore sizes, slower engine speeds and specific maritime operating conditions. Understanding these effects is paramount for the successful adoption of net zero fuels, a topic currently underexplored.
  • Storage and handling: compliance with safety regulations and addressing the challenges of safe storage and handling of liquid ammonia during experimental work has highlighted the need for further research into ammonia liquefaction, fuel integration and safety aspects in future projects.

Impact

The projects have already delivered significant impact across international collaboration, research capacity, technological development, and environmental awareness.

Enhanced collaboration and knowledge transfer

  • Exchange visits: four research exchange visits (two from India and two from the UK) have facilitated the sharing of knowledge and expertise between the partner institutions, with a focus on advanced engine technologies including the Recuperated Split Cycle Engine (RSCE) and RCCI systems.
  • Joint workshops: one online and two in-person International Workshops on Hydrogen and Ammonia brought together key researchers from IIT Bombay, NIT Agartala and the University of Brighton, promoting ongoing collaboration, shared learning, and cross-institutional engagement.
  • Researcher mobility: two PhD students from IIT Bombay and NIT Agartala visited University of Brighton where they undertook a shared experimental programme.

Capacity building in advanced combustion research

  • Training and skill development: practical training in state-of-the-art facilities at the University of Brighton and IIT Bombay has enhanced the skills and expertise of early career researchers, PhD students and research scholars in combustion.
  • Model development: the creation of a merged kinetic model for ammonia/gasoline combustion has improved scientific understanding of alternative fuel blend behaviour in engine systems. The model is a valuable shared resource between the Indian and UK partners.

Technological advancements in fuel combustion

  • Experimental infrastructure: the externally heated diverging channel rig at IIT Bombay enables experiments with both liquid/gaseous fuels, supporting detailed combustion studies essential for validating zero-dimensional simulations of laminar burning velocity and optimising fuel blend ratios.
  • RCCI engine development: the successful installation and commissioning of the RCCI test engine at NIT Agartala has expanded the project’s experimental capability. Ongoing dual-fuel combustion experiments are contributing to the development of sustainable engine technologies, marking a vital step towards the adoption of net-zero fuels.

Environmental impact and awareness

  • The research has advanced understanding of how ammonia/hydrogen fuel blends can be used as sustainable fuels to reduce emissions and improve energy efficiency in RCCI and RSCE engines.
  • Findings highlight strategies for reducing NOx emissions and minimising ammonia slip, thereby supporting the project’s environmental goals.