Call for Abstracts

This work originates from a Japanese Strategic Innovation Promotion (SIP) program and aims to establish a principles‑based framework for engine knock prediction grounded in combustion fundamentals. Using two‑dimensional DNS, a constant‑volume knocking experiment was quantitatively reproduced, marking a key breakthrough. Detailed analysis of the DNS results, combined with theory and targeted experiments, has led to a framework that can predict knock behavior from first principles rather than empirical calibration. Application to PRF mixtures in a CFR engine has already demonstrated encouraging success, and ongoing efforts seek to extend the approach to ammonia‑containing and other future e‑fuel blends. The lecture will summarize the evolution from DNS to reduced predictive metrics, and discuss how such physics‑based indicators can guide the design and optimization of future fuels for high‑efficiency engines.

Since the 2020s, ammonia has attracted renewed attention as a zero-carbon fuel for internal combustion engines, especially for marine and off-road applications. Its distinct thermophysical properties make liquid-phase, high-pressure injection a promising pathway for efficient and cleaner combustion. Under engine-relevant conditions, ammonia sprays often experience flash boiling, which enhances evaporation and atomization but also alters spray penetration and structure. Because ammonia’s calorific value is roughly half that of conventional fuels, larger nozzle diameters and multi-hole injectors are typically required. In multi-hole configurations, plume interactions play a critical role, making it essential to study flash boiling and spray collapse as separate but related phenomena. This work reviews the latest findings on liquid ammonia injection and flash-boiling atomization, emphasizing the need for advanced optical diagnostics at both macroscopic and microscopic scales to support accurate spray modelling and engine design.

Hydrogen is a clean and sustainable energy carrier that is called to play an essential role in future energy systems. Although hydrogen has been used as an industrial gas for decades, its use as an energy carrier would bring it to the proximity of untrained public. This brings additional safety concerns because there are some key differences in the properties of hydrogen and conventional hydrocarbon fuels. To bring all the benefits of hydrogen to our society, hydrogen and its technologies must be safely developed, introduced, and used across a variety of applications and sectors. The presentation will highlight some of the safety issues related to high-pressure gaseous and low-temperature liquid hydrogen. This will be followed by the numerical studies of my team on hydrogen spontaneous ignition, jet fires, explosions and deflagration to detonation transition. The experimental data, either from the literature or collaborators, which were used for model validation in our research, will also be briefly described. Finally, results will be presented from our recent numerical predictions for the internal pressure evolution of a liquid hydrogen tank under fire attack, which was carried out in the frame of a joint industry project on the safety of liquid hydrogen, for which I am the coordinator and scientist in charge.

Ever since its introduction in the 1990s, plasma-assisted combustion has been growing in popularity and influence throughout the research community. Generally favoured for its ability to couple energy into a system over ultrashort (~ nanoseconds) timescales, lack of moving parts, and low energy cost for reactive species production, wide-ranging benefits such as reduction in ignition delay times, flame speed increase, and extension of lean limits are just a few examples of the many reported using this approach. These positive effects are typically achieved by creating a state of non-equilibrium in a combustion system, and taking advantage of this non-equilibrium state between the plasma and combustion chemistry to realize favourable conditions. Understanding, and optimizing this non-equilibrium (for a particular combustion application), which occurs over largely disparate timescales, has necessitated the development of non-intrusive, ultrafast diagnostics for tracking the large spatiotemporal gradients in system properties. This talk will present a few of such laser-based methods such as electric field induced second harmonic generation for electric field measurements, laser induced fluorescence for probing species concentrations and Rayleigh scattering thermometry for measuring temperature. The advent of ultrafast laser systems has been central to this diagnostic development, and the role these light sources play will be discussed and emphasized.

Ammonia (NH₃) is increasingly recognized as a carbon-free energy carrier with high volumetric energy density, established global infrastructure, and the potential to decarbonize sectors where electrification remains challenging. However, using NH₃ directly as a fuel is hindered by poor combustibility, high ignition temperatures, and the risk of significant NOₓ formation. High-temperature catalytic ammonia combustion (HT-CAC) has recently emerged as a promising pathway to address these limitations by coupling surface-mediated NH₃ activation with catalysts engineered to withstand extreme thermal environments.

In this talk, I will introduce our recent advances in HT-CAC and its implications for NH₃-based renewable combustion. First, we showed that Pt single-atom catalysts on refractory oxides can ignite NH₃ slightly above 200 °C and maintain stable combustion up to 1,100 °C while limiting NOₓ emissions to ~50 ppm with no detectable NH₃ slip. This work established single-atom catalysts as an effective design principle for achieving both low ignition and long-term durability.

Building on this concept, we developed a high-entropy fluorite oxide aerogel (HEFOA) that stabilizes Pt through one-pot synthesis, preserving high surface area and structural integrity under 1,200 °C operation. The Pt@HEFOA catalyst delivers sustained activity and excellent N₂ selectivity over extended operation, enabled by lattice disorder and sluggish diffusion that suppress sintering.

Together, these studies demonstrate HT-CAC as a viable next-generation NH₃ utilization strategy capable of providing high-grade, low-NOₓ heat for hard-to-abate industries and supporting a future NH₃-based energy economy.

The International Maritime Organization (IMO) proposed the historic 2050 net-zero greenhouse gas (GHG) target, and the use of carbon-free ammonia is widely acknowledged as one of the most promising pathways to achieve this goal. However, ammonia engines still suffer from low efficiency and high nitrogenous emissions due to ammonia’s inherently poor combustion characteristics. For large low-speed ammonia engines, which typically exhibit high NOx emissions and engine-out NOx levels exceeding unburned NH3, we propose an active in-cylinder DeNOx strategy under high-pressure direct-injection (HPDI) operation. By utilizing liquid ammonia post-injection, the strategy facilitates in-cylinder NOx reduction through selective non-catalytic reduction (SNCR) reactions, thereby mitigating the need for catalysts and aftertreatment systems. The proposed strategy achieves over 40% NOx reduction, meets IMO Tier Ⅲ limits while maintaining high ITE and keeping N2O and unburned NH3 at ultralow levels. For medium- and high-speed ammonia engines, a concept termed as in-cylinder reforming gas recirculation is proposed to simultaneously improve the thermal efficiency and reduce the unburned NH3, NOx, N2O and GHG emissions. For this concept, one cylinder of the multi-cylinder engine operates rich of stoichiometric and the excess ammonia in the cylinder is partially decomposed into hydrogen, then the exhaust of this dedicated reforming cylinder is recirculated into the other cylinders and therefore the advantages of hydrogen-enriched combustion and exhaust gas recirculation can be combined. The results show that the strategy can increase the indicated thermal efficiency by 15.8% and reduce unburned NH3 by 89.3%, N2O by 91.2% compared to the base/traditional ammonia engine without the proposed method. At the same time, it is able to reduce carbon footprint by 97.0% and greenhouse gases by 94.0% compared to the traditional pure diesel mode. The findings offer valuable guidance for the development of ammonia-fueled marine engines and support the sustainable transition to zero-carbon maritime transportation.

The aviation industry contributes approximately 2–3% of global CO₂ emissions and aims to achieve net-zero carbon emissions by 2050. However, the pathway to net zero is highly challenging. Emerging low-carbon energy carriers such as hydrogen, ammonia, and batteries are not yet feasible replacements for jet fuel, particularly for long-haul flights.

Sustainable Aviation Fuel (SAF) is currently the most viable solution, with the potential to reduce aviation emissions by up to 65%. Unfortunately, current SAF supply remains far below expectations. Bio-based SAF accounts for only about 0.2% of global jet fuel consumption and is further constrained by the limited availability and sustainability of biomass feedstocks.

To meet future demand, Power-to-Liquid (PtL) technologies will be essential. PtL provides a scalable, long-term pathway to produce low-carbon SAF and is expected to play a critical role in supporting the aviation industry's decarbonization efforts. At ISCE2, a multidisciplinary team of scientists and engineers, in collaboration with IHI, has developed a novel technology to produce SAF directly from CO₂. In this talk, our work on CO2 to SAF will be introduced.

Achieving net-zero emissions by 2050 calls for coordinated efforts across government, industry, and research communities. Singapore’s national strategy supports this transition through initiatives that enhance energy efficiency, advance low-carbon technologies, and strengthen international collaboration in clean energy, carbon markets, and technology innovation.

Within this broader effort, the energy and chemicals sector remain pivotal, as decarbonisation depends on transitioning from conventional carbon-based fuels toward sustainable alternatives such as ammonia, methanol, and hydrogen. Advancing these pathways requires innovations that span the full value chain—from catalyst development and reactor optimisation to process integration and system deployment.

In this study, we present two complementary technology platforms that leverage digital modelling and AI to accelerate the low-carbon transition: 1. CATPLAT – an AI-assisted catalyst design and screening platform that integrates materials informatics, physics-based modelling, and machine learning to identify and optimise high-performance catalysts. 2. REACT – a multi-scale reactor and combustion modelling platform that couples reaction kinetics, transport phenomena, and fluid dynamics to optimise reactor design and operating parameters. It also incorporates physics-based combustion and flame modelling module, enabling the investigation of flame characteristics and combustion behaviours of alternative fuels for power generation applications.

Together, these platforms provide an end-to-end digital framework linking catalyst discovery to process and reactor optimisation. The combined use of CATPLAT and REACT enables faster evaluation of new catalytic systems, reaction mechanisms, and combustion processes - reducing development time and accelerating deployment of next-generation sustainable fuel technologies.

A case study on hydrogen production from green ammonia illustrates how this integrated framework enhances the understanding of reaction–transport interactions, guides experimental design, and supports data-driven decision-making toward Singapore’s long-term net-zero ambitions.

Recently, ammonia has gained attention as a low-carbon or even carbon-free marine fuel, forming part of the ambitious global efforts to decarbonize maritime transportation through phased approaches set out by the International Maritime Organization (IMO). However, due to its high toxicity, large-scale adoption of ammonia requires careful management of accidental release risks, ensuring that any toxic plume is effectively contained and mitigated before reaching sensitive receptors. Since 2020, MESD has been conducting studies on ammonia bunkering and safety, including the creation and simulation of various release scenarios under tropical marine conditions. This presentation will share the key findings and insights gained from these years of research.

Decarbonised gas turbines are an important lever to enable net zero greenhouse gas emissions – there is potential to achieve significant transformation via the Siemens Energy fleet of over 7000 engines located in more than 90 countries with power outputs ranging from 2 to 593 MW. Research partnerships between governments, industry, and academia provide key insights that are essential to the design of state-of-the-art gas turbines. This presentation will show highlights from R&D programmes for sustainable fuels including hydrogen, methanol, and ammonia.

An integrated industrial power-to-H2-to-power solution has been demonstrated at full scale under the EU HYFLEXPOWER and HYCOFLEX projects, using a Siemens Energy electrolyzer for green H2 production and dry low emissions (DLE) combustion technology on the SGT-400 gas turbine. Successful engine tests with bio-methanol have also been carried out on aero-derivative (nonDLE) SGT-A20 and SGT-A35 gas turbines. Ammonia and ammonia-hydrogen blends have been studied under several research projects with academic partners, including the ongoing LCER-2 project in Singapore. Together with our partners, we are addressing the unique challenges of ammonia combustion in gas turbines, with the aim of providing sustainable power generation for regions where importing ammonia is an attractive route to decarbonization.

Mitsubishi Heavy Industries (MHI), under the theme of “MISSION NET ZERO,” has issued its 2040 Carbon Neutrality Declaration, combining the Group’s technologies and resources to promote this effort. MHI defines the energy transition as encompassing all measures aimed at decarbonizing energy systems that predominantly rely on fossil fuels. These measures are organized around three core pillars: “Decarbonizing Existing Infrastructure”, “Establishing a Hydrogen Ecosystem” and “Establishing a Carbon Dioxide Ecosystem”. Development of combustion equipment and control of combustion phenomena are important for the realization of these goals. MHI has installed many high-efficiency GTCC (Gas Turbine Combined Cycle) plants and WTE (Waste to Energy) plants in Singapore. For the development of hydrogen and ammonia gas turbine combustor and the development of the WTE related combustion technologies, the examples of “Laboratory to Commercial” are presented.